Skimming device for unfreezing solidified molten iron in iron storage type main runner

Abstract

The utility model provides a skimmer for unfreezing solidified molten iron in an iron storage type main runner, the skimmer comprises two joints, a replacement cross beam, a small well and an iron runner, the two joints are oppositely arranged on the two side walls of the main runner, the two ends of the replacement cross beam are respectively connected with the two joints, the replacement cross beam is connected with the small well, and the small well is connected with the iron runner. A distance exists between the replacement cross beam and the upper surface of the solidified molten iron below the replacement cross beam, the width of the replacement cross beam is smaller than that of the connector, the small well is arranged on one side of the replacement cross beam, and the small well is close to one end of the main channel. The small well is communicated with the main channel on the other side of the replacement cross beam through a space below the replacement cross beam, the iron channel is arranged at one end of the main channel, and the iron channel is communicated with the small well. By means of the skimmer, solidified molten iron in the main runner can be rapidly melted, and the normal iron storage and skimming functions of the main runner are recovered.

Description

Technical Field

[0001] This utility model relates to the field of metallurgical engineering technology, and in particular to a skimmer for thawing solidified molten iron in a main trench. Background Technology

[0002] Currently, blast furnace ironmaking processes are all equipped with a storage-type main trough. This main trough integrates the traditional main trough and slag skimmer into a single unit, improving slag-iron separation, extending service life, simplifying operation and maintenance, and significantly reducing worker workload. However, during special furnace conditions such as furnace cooling, hearth freezing, pipeline travel, and furnace start-up and shutdown, the molten iron temperature often becomes very low. If the furnace front work is inadequate, the molten iron in the storage-type main trough may solidify below its melting point due to heat loss, completely losing its function of slag skimming and slag passing. In such cases, the only solution is complete mechanical dismantling and reconstruction, which not only consumes a large amount of manpower and resources but also takes a long time, seriously affecting normal blast furnace production.

[0003] The main channel in the prior art has the following disadvantages:

[0004] 1. When the main ditch loses its function of slag removal and iron ore discharge, it requires the use of large mechanized equipment such as excavators and blasting machines, as well as violent demolition methods. This not only makes the construction process complex but also causes significant damage. It can easily damage large concrete structures such as the iron tapping area where the iron storage main ditch is located, as well as important equipment and facilities near the iron storage main ditch.

[0005] 2. It requires the use of industrial pure oxygen for cutting, which poses safety hazards and environmental pollution;

[0006] 3. The construction time is long. It generally takes more than 15 to 20 days to completely demolish and rebuild the main iron storage trench. This results in the iron taphole where the main iron storage trench is located being unable to be put into production for a long time, which has a significant impact on blast furnace production.

[0007] 4. The solidified molten iron in the main storage trench becomes scrap iron, which requires crushing and dismantling processes for recycling, resulting in high costs and significant losses. Utility Model Content

[0008] The purpose of this invention is to provide a skimmer for thawing solidified molten iron in the main ditch of the iron storage system. This skimmer can quickly melt the solidified molten iron in the main ditch and restore the normal iron storage and skimming functions of the main ditch.

[0009] To achieve the above objectives, this utility model provides the following technical solution:

[0010] A skimmer for defrosting molten iron in a main ditch is disclosed. The skimmer is located at one end of the main ditch, and the molten iron solidifies in both the main ditch and the skimmer. The skimmer includes a joint, a replacement beam, a small well, and an iron ditch. Two joints are provided, which are positioned opposite each other on the two side walls of the main ditch. The two ends of the replacement beam are connected to the two joints respectively. There is a distance between the replacement beam and the upper surface of the solidified molten iron below the replacement beam. The width of the replacement beam is smaller than the width of the joint. The small well is located on one side of the replacement beam, near one end of the main ditch. The small well communicates with the other side of the main ditch through the space below the replacement beam. The iron ditch is located at one end of the main ditch and communicates with the small well.

[0011] Furthermore, in the above-mentioned skimmer for solidified molten iron in the main ditch for thawing and storing iron, the width of the replacement beam is 60% of the width of the joint, and the axis of the replacement beam is collinear with the axis of the joint.

[0012] Furthermore, in the above-mentioned skimmer for solidifying molten iron in the main ditch of the thawing and storage type, the upper surface of the joint, the upper surface of the replacement beam, and the upper surface of the main ditch are all located on the same plane, and the height of the replacement beam is 0.3m.

[0013] Furthermore, in the slag skimmer for solidifying molten iron in the aforementioned thawing and storage trough, the length of the joint is 0.1m.

[0014] Furthermore, in the above-mentioned skimmer for solidified molten iron in the main ditch for thawing and storing iron, the distance between the lower surface of the replacement beam and the upper surface of the solidified molten iron below the replacement beam is greater than or equal to 0.3m.

[0015] Analysis shows that this utility model discloses a skimmer for thawing solidified molten iron in the main trough of an iron storage facility. The skimmer is simple to implement and has low manufacturing costs. Removing the existing crossbeams of the skimmer can be done using a common handheld pneumatic pick or a ditch-removing machine already on site, without needing to bring in excavators or other large machinery from outside the site. Since no large machinery or devices are involved, and no destructive construction methods are used, there is no damage to large concrete structures such as the blast furnace tapping area. The manpower and material resources required for construction are very small, resulting in low costs. It eliminates the need to use industrial pure oxygen to melt the solidified molten iron, avoiding the safety hazards and environmental pollution caused by the generation of dense smoke associated with melting molten iron with industrial pure oxygen. Using this skimmer to thaw solidified molten iron in the main trough of an iron storage facility is not only convenient, quick, safe, and environmentally friendly, but also has a short thawing time, saving time, labor, and minimizing losses. It achieves complete recovery of solidified molten iron in the main trough and skimmer, allowing it to be melted back into ordinary molten steel for reuse, reducing economic losses caused by ironmaking accidents. Attached Figure Description

[0016] The accompanying drawings, which form part of this application, are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an undue limitation of the present invention. Wherein:

[0017] Figure 1 This is a schematic diagram of the structure of an iron storage main trench in the prior art.

[0018] Figure 2 This is a structural schematic diagram of an embodiment of the present utility model.

[0019] Explanation of the attached diagram labels: 1 Main trench; 2 Skimmer; 3 Existing crossbeam; 4 Small well; 5 Solidified molten iron; 6 Replacement crossbeam; 7 Joint; 8 Inlet; 9 Outlet; 10 Iron trench. Detailed Implementation

[0020] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. Various examples are provided by way of explanation of the present invention and not by way of limitation. In fact, those skilled in the art will recognize that modifications and variations can be made to the present invention without departing from the scope or spirit of the invention. For example, a feature shown or described as part of one embodiment may be used in another embodiment to produce yet another embodiment. Therefore, it is desirable that the present invention encompass such modifications and variations that fall within the scope of the appended claims and their equivalents.

[0021] In the description of this utility model, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," and "bottom," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this utility model and do not require that this utility model be constructed and operated in a specific orientation; therefore, they should not be construed as limitations on this utility model. The terms "connected," "linked," and "set up" used in this utility model should be interpreted broadly. For example, they can refer to a fixed connection or a detachable connection; a direct connection or an indirect connection through intermediate components; a wired connection, a radio connection, or a wireless communication signal connection. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0022] The accompanying drawings illustrate one or more examples of the present invention. The detailed description uses numerals and letters to refer to features in the drawings. Similar or analogous reference numerals in the drawings and description have been used to refer to similar or analogous parts of the present invention. As used herein, the terms “first,” “second,” and “third,” etc., are used interchangeably to distinguish one component from another and are not intended to indicate the location or importance of individual components.

[0023] like Figures 1 to 2 As shown, according to an embodiment of this utility model, a skimmer for defrosting solidified molten iron in a main ditch is provided. The skimmer 2 is set at one end of the main ditch 1. The molten iron is solidified in both the main ditch 1 and the skimmer 2. The skimmer 2 includes a joint 7, a replacement beam 6, a small well 4, and an iron ditch 10. There are two joints 7, which are set opposite each other on the two side walls of the main ditch 1. The two ends of the replacement beam 6 are respectively connected to the two joints 7. There is a distance between the replacement beam 6 and the upper surface of the solidified molten iron 5 below the replacement beam 6. The width of the replacement beam 6 is smaller than the width of the joint 7. The small well 4 is set on one side of the replacement beam 6, and the small well 4 is closer to the end of the main ditch 1 than the replacement beam 6. The small well 4 is connected to the other side of the main ditch 1 through the space below the replacement beam 6. The iron ditch 10 is set at one end of the main ditch 1 and is connected to the small well 4.

[0024] Furthermore, the width of the replacement beam 6 is 60% of the width of the joint 7, and the axis of the replacement beam 6 is collinear with the axis of the joint 7. That is, the width of the replacement beam 6 is 40% smaller than the width of the joint 7, creating an inlet 8 and an outlet 9 on both sides of the replacement beam 6 for the flow of high-temperature molten iron. This arrangement allows high-temperature molten iron to flow from the inlet 8 into the space below the replacement beam 6 and out through the outlet 9, thereby enabling the high-temperature molten iron to melt the solidified molten iron 5 in the main channel 1 and the skimmer 2. The upper surfaces of the joint 7, the replacement beam 6, and the main channel 1 are all located on the same plane. The height of the replacement beam 6 is 0.3m. The length of the joint 7 is 0.1m. The distance between the lower surface of the replacement beam 6 and the upper surface of the solidified molten iron 5 below the replacement beam 6 is greater than or equal to 0.3m.

[0025] like Figure 1As shown, the existing iron storage main trough 1 in the prior art is equipped with an existing crossbeam 3. During special furnace conditions such as furnace cooling, hearth freezing, pipe travel, and furnace start-up and shutdown, the molten iron temperature often becomes very low. If the furnace front work is inadequate at this time, all spaces below the iron trough 10 level, including the main trough 1, the slag skimmer 2, and the existing crossbeam 3 on both sides and in the depth direction above the slag skimmer 2, will be filled with solidified molten iron 5. Due to the lack of space, the molten iron smelted in the blast furnace cannot pass through the main trough 1 for slag skimming. The main trough 1 then completely loses its function, causing the blast furnace taphole where the iron storage main trough 1 is located to be unable to produce iron.

[0026] like Figure 2 As shown, a portion of the existing crossbeam 3 is removed, and then a replacement crossbeam 6 is poured into the pit where the existing crossbeam 3 was removed. The width, height, and length of the replacement crossbeam 6 are all smaller than those of the existing crossbeam 3, so that the space on both sides and below the replacement crossbeam 6 forms a channel for the flow of high-temperature molten iron.

[0027] For example, in the existing technology of the main trough 1 for iron storage, the existing crossbeam 3 has a length of 1.0m, a width of 0.8m, and a height of 0.7m. The width of the replacement crossbeam 6 is 0.48m (60% of the width of the existing crossbeam 3). 20% of the width of the existing crossbeam 3 on one side of the replacement crossbeam 6 is used as the inlet 8 for high-temperature molten iron, and 20% of the width of the existing crossbeam 3 on the other side of the replacement crossbeam 6 is used as the outlet 9 for high-temperature molten iron. The length of the replacement crossbeam 6 is 0.8m, and 0.1m of length is reserved at each end of the existing crossbeam 3 as joints 7 for casting the replacement crossbeam 6. In the depth direction, all refractory materials of the existing crossbeam 3 are removed until solidified molten iron 5 is reached. If the refractory material has high rigidity and cannot be completely removed, in the height direction of the existing crossbeam 3, it must be removed to a height of at least 0.6m below the upper surface of the existing crossbeam 3. The height of the cast replacement crossbeam 6 is 0.3m, so that there is a space of greater than or equal to 0.3m below the cast replacement crossbeam 6 for a channel for the flow of high-temperature molten iron.

[0028] When the temperature of the molten iron smelted in the blast furnace rises above 1450℃, the main trough 1, which has been manufactured and baked with replacement crossbeam 6, can be used. The high-temperature molten iron above 1450℃ flows in the main trough 1 containing solidified molten iron 5, passes through the inlet 8 of the skimmer 2, passes below the replacement crossbeam 6, then rises in the outlet 9 of the skimmer 2 and overflows from the small well 4, flowing into the iron trough 10. Under the melting effect of the molten iron at temperatures above 1450℃, the solidified molten iron 5 will melt and flow away, restoring the normal iron storage and skimming functions of the main trough 1.

[0029] The method for thawing solidified molten iron in the main iron storage trench using the above-mentioned skimmer includes the following steps:

[0030] Step 1, remove the existing crossbeam 3: Use equipment such as pneumatic picks and trenching machines to remove the existing crossbeam 3 on the skimmer 2 in the main trench 1. Leave 0.1m of refractory material at each end of the existing crossbeam 3 along its length as joints 7 for casting the replacement crossbeam 6; remove all the refractory material along the height of the existing crossbeam 3 until solidified molten iron 5 can be seen in the depth direction; if the refractory material has high rigidity and cannot be completely removed, it should be removed at least to a height of 0.6m below the upper surface of the existing crossbeam 3.

[0031] Step 2, Casting the Replacement Beam 6: A replacement beam 6 is cast at the location of the existing beam 3 using a mold. The main trench refractory is used to cast the replacement beam 6 through the mold, which is made of steel plate with a thickness of 1-3 mm (e.g., 1mm, 2mm, 3mm). The size of the replacement beam 6 is smaller than the size of the existing beam 3. The cast replacement beam 6 is then baked for at least 6 hours. After the existing beam 3 is removed, the mold is installed. The mold is made of steel plate with a thickness of 1-3 mm, according to the size of the replacement beam 6, and installed in the pit after the removal of the existing beam 3. After the mold is installed, the main trench refractory is used to cast the replacement beam 6. The cast replacement beam 6 is then baked. After the replacement beam 6 is dried, the replacement beam 6 is complete. The replacement beam 6 is then connected to the skimmer 2 of the main trench 1 via a connector 7. The main trench 1 is replaced by casting the refractory material of the main trench 1 through a mold. Because the amount of refractory material used is small, the main trench 1 can be put into use after the baking time of the replacement beam 6 is 6 hours.

[0032] Step 3: Pour the high-temperature molten iron from the blast furnace into the main trough 1. The high-temperature molten iron melts the solidified molten iron 5 in the main trough 1 and the skimmer 2, restoring the normal iron storage and skimming functions of the main trough 1. The temperature of the high-temperature molten iron used to melt the solidified molten iron is greater than 1450℃. After the solidified molten iron 5 in the main trough 1 is completely melted and its normal iron storage and skimming functions are restored, no further maintenance is required for the main trough 1; it can be used directly according to normal production procedures.

[0033] The iron storage capacity of a typical 2000-ton blast furnace main trough 1 is approximately 20 tons. The heat required to melt 20 tons of solidified molten iron 5 is 20(t) × 1279(mJ / t) = 25580(mJ) (melting 1 ton of iron requires approximately 1279 mJ of heat). When molten iron at a high temperature above 1450℃ flows through the main trough 1 containing solidified molten iron 5 and the skimmer 2, the temperature drops by approximately 50℃, releasing heat of 0.46(mJ / t·℃) × 50(℃) = 23(mJ / t) (the specific heat capacity of iron is 0.46 mJ / t·℃). Therefore, the total amount of molten iron above 1450℃ required to completely melt the solidified molten iron 5 is approximately 25580(mJ) ÷ 23(mJ / t) ≈ 1110(t). Based on a typical output of 500 tons of iron per heat for a 2000-class blast furnace, after three heats of iron are used consecutively, the solidified molten iron 5 in the main iron storage trough 1 and the slag skimmer 2 can be completely melted and flowed away, restoring the iron storage and slag skimming function of the main iron storage trough 1. For blast furnaces of different volumes, the calculation can be extrapolated in this way based on the different iron capacity of the main iron storage trough 1 and the average output of iron per heat.

[0034] After the solidified molten iron 5 in the main iron storage trench 1 and the slag skimmer 2 is completely melted and flowed away, restoring normal iron storage and slag skimming functions, no further maintenance is required. It can be used directly according to normal production methods. There is no need to drain the molten iron in the main trench 1 for repair and recasting. It will remain in use until it reaches the normal corrosion standard requiring maintenance, at which point it will be taken out of service for maintenance.

[0035] This skimmer uses molten iron smelted by the blast furnace itself to melt the solidified molten iron 5 in the main trough 1 and skimmer 2, thus restoring the normal iron storage and skimming functions of the main trough 1. No external equipment or devices are required. Generally, dismantling the existing crossbeam 3 takes about 6-8 hours, casting a replacement crossbeam 6 takes about 1 hour, and baking takes about 6 hours, making it ready for use in about 13-15 hours. During special furnace conditions, the main trough 1 can generally be completely thawed within 24 hours. Using this skimmer to thaw the solidified molten iron in the main trough is simple and time-saving, has minimal impact on normal blast furnace production, avoids safety hazards and environmental pollution factors such as the use of industrial pure oxygen, and ensures that all solidified molten iron 5 is recovered and reused in a normal production manner, resulting in no economic loss. After the solidified molten iron 5 is completely thawed, the main trough 1 can still withstand the load of normal blast furnace production, completing the next generation of main trough 1's lifespan under normal production conditions.

[0036] As can be seen from the above description, the embodiments of this utility model achieve the following technical effects:

[0037] 1. The slag skimmer is simple to implement and has low manufacturing costs. When dismantling the existing crossbeam 3 of the slag skimmer 2, a common handheld pneumatic pick or a trenching machine already on-site can be used; there is no need to bring in excavators or other large machinery from outside the site. Because no large machinery or devices are involved, and no destructive construction methods are used, there is no damage to large concrete structures such as the blast furnace tapping area. The manpower and material resources required for construction are very small, resulting in low costs.

[0038] 2. It eliminates the need to use industrial pure oxygen to melt solidified molten iron, thus avoiding safety hazards and environmental pollution caused by the generation of dense smoke from industrial pure oxygen. Using this skimmer to thaw solidified molten iron in the main storage ditch is not only convenient, fast, safe, and environmentally friendly, but also has a short thawing time, saving time and labor with minimal losses.

[0039] 3. It enables the complete recovery of solidified molten iron 5 in the main channel 1 and skimmer 2, which is then melted back into ordinary molten iron for use, thus reducing the economic losses caused by ironmaking accidents.

[0040] The above are merely preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A skimmer for thawing molten iron solidified in a main ditch, wherein the skimmer is disposed at one end of the main ditch, and the molten iron solidifies both in the main ditch and in the skimmer, characterized in that, The skimmer includes a connector, a replacement crossbeam, a small well, and an iron trough, wherein... Two connectors are provided, and the two connectors are arranged opposite each other on the two side walls of the main trench. The two ends of the replacement beam are respectively connected to the two joints. There is a distance between the replacement beam and the upper surface of the solidified molten iron below it. The width of the replacement beam is smaller than the width of the joint. The small well is located on one side of the replacement beam, near one end of the main trench. The small well is connected to the main trench on the other side of the replacement beam through the space below the replacement beam. The iron trench is located at one end of the main trench and is connected to the small well.

2. The skimmer for thawing solidified molten iron in the main trench as described in claim 1, characterized in that, The width of the replacement beam is 60% of the width of the joint, and the axis of the replacement beam is collinear with the axis of the joint.

3. The skimmer for thawing solidified molten iron in the main ditch as described in claim 1, characterized in that, The upper surface of the connector, the upper surface of the replacement beam, and the upper surface of the main trench are all located on the same plane, and the height of the replacement beam is 0.3m.

4. The skimmer for thawing solidified molten iron in the main trench as described in claim 1, characterized in that, The length of the connector is 0.1m.

5. The skimmer for thawing solidified molten iron in the main trench as described in claim 1, characterized in that, The distance between the lower surface of the replacement beam and the upper surface of the solidified molten iron below the replacement beam is greater than or equal to 0.3m.

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