A device for reducing the radiation heat loss of molten iron during tapping of a blast furnace

Abstract

The utility model provides a device for reducing the radiation heat loss of molten iron during the tapping of blast furnace, which comprises a molten iron shielding and heat preserving device; the molten iron shielding and heat preserving device is arranged between each oscillating flow nozzle and the molten iron ladle directly below the oscillating flow nozzle; the molten iron shielding and heat preserving device is a hollow structure from top to bottom, and comprises a front baffle, a side straight plate, a rear baffle and a side arc plate connected in sequence; the side arc plate is located on the outer side of the molten iron shielding and heat preserving device; an upper portion of the side straight plate is provided with a molten iron gap; in the utility model, the molten iron shielding and heat preserving device makes the molten iron flow in a relatively closed space pipeline into the molten iron ladle, reduces the radiation heat transfer of the molten iron below the flow nozzle, controls the heat loss during the tapping process, improves the temperature of the molten iron in the converter, and achieves the purpose of green environmental protection, energy saving and safety.

Description

Technical Field

[0001] This utility model relates to the field of thermal energy conservation technology, and more specifically, to a device for reducing radiant heat loss of molten iron during tapping from a blast furnace. Background Technology

[0002] When tapping iron from a blast furnace in steel plants, the molten iron flowing between the oscillating nozzle and the ladle is exposed to the natural environment without any insulation or protection, causing a rapid drop in temperature, typically 50-80°C, accounting for 27%-43% of the total temperature loss at the iron-steel interface. Simultaneously, molten iron splashing during tapping damages the side walls and roof of the work area, forcing shunting personnel to work in harsh conditions at the risk of burns. This underscores the necessity of improving insulation during molten iron transportation.

[0003] To reduce heat loss, various methods have been developed in the industry. For example, one molten iron insulation device incorporates a collection hood, a molten iron isolation hood, and an auxiliary suction system. The collection hood is suspended below the swing chute, reducing the contact area between the molten iron and air, thus lowering temperature loss and improving the safety and environmental performance of tapping operations. Another insulation device for blast furnace tapping uses a combination design of a dust collection hood, a molten iron isolation device, and suction pipes to optimize heat insulation and deformation resistance, while also improving the viewing angle for observing molten iron flow and facilitating operational control.

[0004] Existing methods have significant shortcomings. On the one hand, the devices are complex in structure and bulky in equipment, resulting in high manufacturing and installation costs and limiting their practical application feasibility. On the other hand, these methods are mostly one-off experimental schemes and have not been applied to actual production for long periods, thus lacking practicality. Some devices also require large-scale modifications to existing equipment, which involves significant investment and may disrupt the original process flow, limiting their widespread promotion and application in the steel industry. Utility Model Content

[0005] This invention provides a device for reducing radiative heat loss of molten iron during tapping in a blast furnace, thereby solving the problem of poor efficiency in existing methods for reducing heat loss.

[0006] The technical means adopted in this utility model are as follows: A device for reducing radiant heat loss of molten iron during tapping in a blast furnace includes a molten iron shielding and insulation device and a secondary heat radiation shielding device. The molten iron shielding and heat preservation device is installed between each oscillating spout and the molten iron ladle directly below the oscillating spout; the molten iron shielding and heat preservation device is a hollow structure that runs through from top to bottom, and the molten iron shielding and heat preservation device includes a front baffle, a side straight plate, a rear baffle and a side arc plate connected in sequence, and the side arc plate is located on the outside of the molten iron shielding and heat preservation device; the upper part of the side straight plate has a molten iron notch; The molten iron heat preservation device is provided with a secondary heat radiation shielding device on the outside. The secondary heat radiation shielding device includes a first horizontal shielding plate, a second horizontal shielding plate, a first vertical shielding plate, and a second vertical shielding plate. The outer side of the front baffle is connected to the first horizontal shielding plate, the outer side of the rear baffle is connected to the second horizontal shielding plate, the left side of the first horizontal shielding plate and the second horizontal shielding plate is connected to the right side of the first vertical shielding plate, the right side of the first horizontal shielding plate and the second horizontal shielding plate is connected to the left side of the second vertical shielding plate, and the front and rear sides of the first vertical shielding plate and the second vertical shielding plate are respectively connected to the lower edge of the blast furnace platform.

[0007] Furthermore, the inner wall of the molten iron shielding and insulation device is provided with a layer of knotted refractory material.

[0008] Furthermore, the inner side of the knotted refractory material layer is coated with a high-temperature resistant coating layer.

[0009] Furthermore, the upper part of the secondary heat radiation shielding device is higher than the upper part of the molten iron shielding and insulation device, and the lower part of the secondary heat radiation shielding device is lower than the lower part of the molten iron shielding and insulation device.

[0010] Furthermore, an oscillating spout is provided above the lower edge of the blast furnace platform, and a molten iron ladle is provided below the lower edge of the blast furnace platform, with the molten iron ladle located on the main and auxiliary passages below the blast furnace platform.

[0011] Furthermore, the diameter of the hollow structure of the molten iron shielding and heat preservation device is the maximum outer diameter of the molten iron stream being insulated; the height of the molten iron shielding and heat preservation device is equal to the distance between the lower part of the swing nozzle and the upper part of the molten iron ladle opening.

[0012] The side arc plate protrudes away from the direction of the swing nozzle.

[0013] Compared with the prior art, the present invention has the following advantages: This utility model's molten iron shielding and heat preservation device allows molten iron to flow into the molten iron ladle within a relatively enclosed space pipe, reducing radiative heat transfer of the molten iron below the spout, controlling heat loss during the tapping process, increasing the temperature of molten iron in the converter, and achieving the goals of green, environmentally friendly, energy-saving, and safe operation.

[0014] In this invention, the secondary thermal radiation shielding device provides a second layer of thermal radiation shielding for the molten iron flowing through the molten iron shielding and heat preservation device, further reducing the radiative heat transfer of the molten iron below the spout.

[0015] Production application results show that the use of shielding and insulation devices reduces slag and iron splashing during blast furnace tapping, improves the production environment of the blast furnace tapping area, and increases the temperature of molten iron. At the same time, the device effectively avoids the damage to the surrounding environment and workers caused by iron sparks splashing during tapping. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model 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 some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is the front view of the present utility model.

[0018] Figure 2 for Figure 1 Sectional view of plane AA.

[0019] Figure 3 This is a top view of the present invention.

[0020] Figure 4 This is a schematic diagram of the installation position of this utility model.

[0021] In the diagram: 1. Swinging spout; 2. Ladle; 3. Front baffle; 4. Side straight plate; 5. Rear baffle; 6. Side arc plate; 7. Molten iron notch; 8. First horizontal shielding plate; 9. Second horizontal shielding plate; 10. First vertical shielding plate; 11. Second vertical shielding plate; 12. Lower edge of blast furnace platform; 13. Knotted refractory material layer; 14. Main and auxiliary passages under blast furnace platform; 15. Molten iron shielding and insulation device. Detailed Implementation

[0022] It should be noted that, where there is no conflict, the embodiments and features in the embodiments of this utility model can be combined with each other. The present utility model will now be described in detail with reference to the accompanying drawings and embodiments.

[0023] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit this utility model or its application or use. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0024] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to the present invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0025] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0026] In the description of this utility model, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is usually based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this utility model and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this utility model. The directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0027] For ease of description, spatial relative terms such as "above," "over," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation besides the orientation of the device as described in the figures. For example, if the device in the figures is inverted, a device described as "above" or "above" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0028] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be construed as limiting the scope of protection of this utility model.

[0029] like Figure 1-4 As shown, this utility model provides a device for reducing radiative heat loss of molten iron during tapping in a blast furnace, including a molten iron shielding and heat preservation device 15 and a secondary heat radiation shielding device. The molten iron shielding and insulation device 15 is disposed between each oscillating nozzle 1 and the molten iron ladle 2 directly below the oscillating nozzle 1; the oscillating nozzle 1 is disposed above the lower edge 12 of the blast furnace platform, and the molten iron ladle 2 is disposed below the lower edge 12 of the blast furnace platform, with the molten iron ladle 2 located on the main and auxiliary passages 14 below the blast furnace platform. The molten iron shielding and insulation device 15 is a hollow structure that runs from top to bottom, and includes a front baffle 3, a side straight plate 4, a rear baffle 5, and a side arc plate 6 connected in sequence, with the side arc plate 6 located on the outer side of the molten iron shielding and insulation device 15; the side arc plate 6 protrudes away from the oscillating nozzle 1. A molten iron notch 7 is provided at the upper part of the side straight plate 4; a knotted refractory material layer 13 is disposed on the inner wall of the molten iron shielding and insulation device 15. The inner side of the knotted refractory material layer 13 is sprayed with a high-temperature resistant coating layer.

[0030] The diameter of the hollow structure of the molten iron shielding and heat preservation device 15 is the maximum outer diameter of the molten iron stream being insulated; the height of the molten iron shielding and heat preservation device 15 is equal to the distance between the lower part of the swing nozzle 1 and the upper part of the molten iron ladle 2.

[0031] The molten iron heat preservation device is provided with a secondary heat radiation shielding device on the outside. The secondary heat radiation shielding device includes a first horizontal shielding plate 8, a second horizontal shielding plate 9, a first vertical shielding plate 10, and a second vertical shielding plate 11. The outer side of the front baffle 3 is connected to the first horizontal shielding plate 8, and the outer side of the rear baffle 5 is connected to the second horizontal shielding plate 9. The left sides of the first horizontal shielding plate 8 and the second horizontal shielding plate 9 are connected to the right side of the first vertical shielding plate 10, and the right sides of the first horizontal shielding plate 8 and the second horizontal shielding plate 9 are connected to the left side of the second vertical shielding plate 11. The front and rear sides of the first vertical shielding plate 10 and the second vertical shielding plate 11 are respectively connected to the lower edge 12 of the blast furnace platform. The upper part of the secondary thermal radiation shielding device is higher than the upper part of the molten iron shielding and heat preservation device 15, and the lower part of the secondary thermal radiation shielding device is lower than the lower part of the molten iron shielding and heat preservation device 15.

[0032] This invention provides a device for reducing radiative heat loss of molten iron during tapping in a blast furnace. The structural features of this technology are described in conjunction with the accompanying drawings. In a conventional blast furnace tapping process, molten iron enters the swing nozzle 1 along the lower edge 12 of the blast furnace platform. The swing nozzle alternately pours molten iron into the ladles 2 parked side-by-side on the main and auxiliary runners 14 below the blast furnace platform. Once one ladle 2 has finished tapping, it moves to a different position, and a replacement ladle 2 is subsequently added by a railway locomotive. This ensures that there is always a ladle 2 below the swing nozzle 1 along the lower edge 12 of the blast furnace platform to receive molten iron, achieving continuous and safe tapping. There are currently no insulation or protective measures below the oscillating nozzle 1. The lower edge of the blast furnace platform (12) is at an elevation of 7.30 meters. During tapping, the opening of the oscillating nozzle 1 is 1.10 meters higher than the lower edge of the platform. The opening of the ladle 2 is at an elevation of 4.9 meters, and the bottom of the ladle 2 is at an elevation of 0.9 meters. During tapping, a 3.5-meter-long stream of molten iron is exposed to the natural environment. The molten iron released from the oscillating nozzle 1 during tapping is in direct contact with the atmosphere before reaching the ladle 2, without any insulation or protective measures. Combined with the pouring action of the molten iron and the strong impact of the molten iron on the oscillating nozzle 1 and ladle 2, the generation of smoke, dust, and slag is particularly severe, creating an extremely harsh environment with slag and iron splashing, posing significant challenges to environmental protection and safety. In addition to high-temperature heat radiation, convective heat loss is also significant, with the molten iron temperature dropping by 50-80°C, accounting for 27%-43% of the total interface temperature loss. This invention provides a molten iron shielding and insulation device 15 between the swing nozzle 1 and the molten iron ladle 2 on the lower edge 12 of the blast furnace platform. This device wraps and shields the molten iron that is exposed to the natural environment without any insulation or protection measures between the swing nozzle 1 and the molten iron ladle 2 on the lower edge 12 of the blast furnace platform, allowing the molten iron to flow into the molten iron ladle 2 in a relatively closed space. This reduces the temperature loss of the molten iron and reduces slag and iron splashing, achieving the goals of green environmental protection, energy saving and safety.

[0033] The working process of this utility model is as follows: After the blast furnace taps iron, the molten iron enters the swing nozzle 1. Before entering the molten iron ladle 2, which is parked side by side on the main and auxiliary channels 14 under the blast furnace platform, the molten iron is first wrapped and insulated by the molten iron shielding and heat preservation device 15 set between the swing nozzle 1 and the molten iron ladle 2 on the lower edge 12 of the blast furnace platform. The molten iron exposed to the natural environment without any heat preservation and protection measures between the swing nozzle 1 and the molten iron ladle 2 on the lower edge 12 of the blast furnace platform is protected and insulated. This allows the molten iron to flow into the molten iron ladle 2 in a relatively closed space, which increases the heat preservation and protection measures for the molten iron, restricts the direct contact between the molten iron and the atmosphere, and limits the smoke and dust drift and slag and iron splashing caused by the impact of the molten iron flow with the swing nozzle 1 and the molten iron ladle 2.

[0034] The knotted refractory material layer 13 is a knotted refractory material used to ensure that the molten iron shielding and insulation device 15 prevents the high temperature of the molten iron stream it encloses and avoids damage from smoke and dust and slag splashing. Its long-term service temperature is not lower than 1750℃.

[0035] The molten iron shielding and insulation device 15 is a core method for solving the aforementioned problems by insulating the molten iron stream exposed to the natural environment during tapping. Its insulation capacity design is based on the changes in the internal energy of the molten iron. Through thermal simulation of the process of molten iron flowing from the tapping nozzle to the ladle during the blast furnace tapping process, it restricts convection and radiation heat loss from the surface of the molten iron stream to achieve insulation. The following energy balance equation is established:

[0036] The heat dissipation process of molten iron exposed to the natural environment during tapping can be equated to the heat dissipation process of a cylinder composed of molten iron.

[0037] The molten iron shielding and insulation device 15 resembles an elongated elliptical cylinder, protruding from the upper edge of the box body, with its upper opening close to the swing nozzle to receive the molten iron. Therefore:

[0038] Based on the above principles and calculation formulas, the effectiveness of heat preservation methods to reduce radiative heat loss of molten iron during tapping in the blast furnace is calculated, and the heat preservation capacity is evaluated and engineering design is carried out.

[0039] Example A blast furnace in a certain plant has three conventional tapping outlets. The distance between the bottom of the oscillating spout and the molten iron ladle is 3.5 meters, without any insulation or protective measures. During tapping, the molten iron is poured into the ladles on the main and auxiliary tracks below the blast furnace platform in turn via the oscillating spout. The molten iron is exposed to the natural environment during tapping, and the pouring and impact of the molten iron causes slag and iron to splash, creating an extremely harsh environment. Slag and iron piles up on the side walls and roof of the tapping area, affecting ladle car operation and threatening the safety of locomotive operators. Simultaneously, the molten iron temperature drops rapidly due to heat radiation loss. In August 2023, a device was developed to reduce radiative heat loss of molten iron during blast furnace tapping. This device encloses the molten iron flowing from the oscillating spout, transforming the originally open space into a semi-enclosed space. This reduces the heat exchange area of ​​the molten iron below the spout, reduces temperature loss, and prevents and reduces slag and iron splashing from the small molten iron stream at the beginning and end of tapping, thus solving the problem of heat loss caused by high-temperature heat radiation in the molten iron. The molten iron shielding device is installed on the outside of the spout. It has a metal shell and is lined with heat-insulating and refractory materials. It has the ability to resist high-temperature radiation, splash erosion and high-temperature baking of molten iron. A safety space is reserved above the ladle opening to facilitate the passage of molten iron ladles and locomotives.

[0040] Iron flow shielding device structural dimensions (length × width × height): less than 8540 × 8060 × 2450 mm; wall thickness: 100 mm. Installation parameters: the lower edge is 150 mm away from the edge of the molten iron ladle, the middle edge is connected to the bottom steel structure of the swing nozzle, and the upper edge is flush with the upper surface of the swing nozzle.

[0041] The structural dimensions and installation parameters meet the safety requirements for on-site operation and the passage of locomotives and ladle cars, ensuring on-site iron tapping safety and the passage conditions for both types of molten iron ladles and railway locomotives.

[0042] Implementation results: When this device was used to reduce the radiant heat loss of molten iron during the tapping process in the blast furnace, the temperature difference between the molten iron tapping trough and the ladle mouth was 30.1℃, while the temperature difference was 37.8℃ when this method was not used, thus increasing the molten iron temperature by 7.7℃. At the same time, it limited the splashing of slag and iron during the tapping process in the blast furnace and improved the production environment of the blast furnace tapping area.

[0043] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. A device for reducing radiant heat loss of molten iron during tapping from a blast furnace, characterized in that: Including a molten iron shielding and insulation device (15) and a secondary heat radiation shielding device; The molten iron shielding and heat preservation device (15) is located between each swing nozzle (1) and the molten iron ladle (2) directly below the swing nozzle (1); the molten iron shielding and heat preservation device (15) is a hollow structure that runs through from top to bottom; the molten iron shielding and heat preservation device (15) includes a front baffle (3), a side straight plate (4), a rear baffle (5) and a side arc plate (6) connected in sequence; the side arc plate (6) is located on the outside of the molten iron shielding and heat preservation device (15); the upper part of the side straight plate (4) is provided with a molten iron notch (7). The molten iron heat preservation device is provided with a secondary heat radiation shielding device on the outside. The secondary heat radiation shielding device includes a first horizontal shielding plate (8), a second horizontal shielding plate (9), a first vertical shielding plate (10), and a second vertical shielding plate (11). The outer side of the front baffle (3) is connected to the first horizontal shielding plate (8), the outer side of the rear baffle (5) is connected to the second horizontal shielding plate (9), the left side of the first horizontal shielding plate (8) and the second horizontal shielding plate (9) is connected to the right side of the first vertical shielding plate (10), the right side of the first horizontal shielding plate (8) and the second horizontal shielding plate (9) is connected to the left side of the second vertical shielding plate (11), and the front and rear sides of the first vertical shielding plate (10) and the second vertical shielding plate (11) are respectively connected to the lower edge (12) of the blast furnace platform.

2. The device for reducing radiant heat loss of molten iron during tapping in a blast furnace according to claim 1, characterized in that, The inner wall of the molten iron shielding and heat preservation device (15) is provided with a knotted refractory material layer (13).

3. The device for reducing radiant heat loss of molten iron during tapping in a blast furnace according to claim 2, characterized in that, The inner side of the knotted refractory material layer (13) is coated with a high-temperature resistant coating layer.

4. The apparatus for reducing radiant heat loss of molten iron during tapping from a blast furnace according to claim 1, characterized in that, The upper part of the secondary thermal radiation shielding device is higher than the upper part of the molten iron shielding and insulation device (15), and the lower part of the secondary thermal radiation shielding device is lower than the lower part of the molten iron shielding and insulation device (15).

5. The apparatus for reducing radiant heat loss of molten iron during tapping from a blast furnace according to claim 1, characterized in that, A swing nozzle (1) is provided above the lower edge (12) of the blast furnace platform, and a molten iron ladle (2) is provided below the lower edge (12) of the blast furnace platform. The molten iron ladle (2) is located on the main and auxiliary passages (14) under the blast furnace platform.

6. The apparatus for reducing radiant heat loss of molten iron during tapping from a blast furnace according to claim 1, characterized in that, The diameter of the hollow structure of the molten iron shielding and heat preservation device (15) is the maximum outer diameter of the molten iron stream being insulated; the height of the molten iron shielding and heat preservation device (15) is equal to the distance between the lower part of the swing nozzle (1) and the upper part of the molten iron ladle (2).

7. The apparatus for reducing radiant heat loss of molten iron during tapping in a blast furnace according to claim 1, characterized in that, The side arc plate (6) protrudes away from the swing nozzle (1).

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