Blast furnace tapping main channel with remote skimmer

Abstract

The invention belongs to the technical field of metallurgical ironmaking equipment, and relates to a slag skimmer remote type blast furnace tapping main channel which is arranged on a tapping house platform and comprises a first main channel section, a second main channel section and a slag skimmer. The first main channel section and the second main channel section are arranged in a right-angle or obtuse-angle lap joint mode so as to increase the total length of the blast furnace tapping main channel. And the skimmer is arranged at the tail end of the second main channel section. Through the right-angle or obtuse-angle lap joint of the first main channel section and the second main channel section and the linear or curved design of the second main channel section, the total length of the main channel is flexibly prolonged, the slag-iron separation time is effectively prolonged, and therefore the separation efficiency is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of metallurgical ironmaking equipment and relates to a blast furnace iron tapping main ditch with a remote-mounted slag skimmer. Background Art

[0002] In the blast furnace ironmaking process, the main ditch, as a core facility, undertakes the important task of separating liquid iron from slag. The rationality of its structural parameters (length, width, and depth) plays a decisive role in the slag-iron separation effect. The main ditch length specifically refers to the distance from the taphole reference point to the slag skimmer. This parameter is crucial in the slag-iron separation process. A reasonable length can provide sufficient separation time and space for the slag and iron, allowing the molten iron and slag to be fully stratified, thereby improving separation efficiency. However, the determination of the main ditch length is not entirely determined by process requirements. It is also limited by practical factors such as the size of the iron-making platform and the layout of the molten iron transportation line.

[0003] Generally speaking, there is a close correlation between the volume of the blast furnace and the tapping speed and the length of the main trench. The larger the volume of the blast furnace, the more molten iron and slag are produced per unit time, and the faster the tapping speed is, generally between 3-8t / min. In order to adapt to this high-output and high-flow rate operating condition and ensure that the slag and iron can be fully separated, the length of the main trench needs to be increased accordingly, usually in the range of 7-19m. This is because a longer main trench can extend the residence time of the slag and iron in the trench, allowing the denser molten iron sufficient time to settle to the bottom of the trench, while the less dense slag floats on the surface of the molten iron, thus achieving effective separation. A reasonable main trench length that is compatible with the blast furnace volume can not only significantly improve the slag and iron separation efficiency, but also have a positive impact on the main trench itself, extending its service life, reducing the consumption of refractory materials, and lowering production costs.

[0004] However, in actual blast furnace expansion and overhaul projects, the challenge of limited space is often encountered. As the blast furnace capacity increases, conventional design concepts dictate that the main trench length also needs to increase accordingly to meet the requirements for slag-iron separation. However, due to limited space around the casthouse, the main trench length cannot be increased as expected. Maintaining the original main trench length in this situation would lead to a series of serious problems. On the one hand, the slag-iron separation effect would be significantly deteriorated, and more molten iron would be mixed with the slag. This would not only increase the difficulty of subsequent processing but also pose certain safety risks, such as the possibility of blasting during slag water quenching. On the other hand, iron loss would increase significantly, resulting in a large amount of iron resources being wasted, thereby reducing the company's economic benefits.

[0005] Therefore, how to optimize the main ditch design and ensure effective slag and iron separation when the blast furnace is expanded and the site is limited has become a technical problem that needs to be solved urgently in the current blast furnace ironmaking field. Summary of the Invention

[0006] In view of this, the purpose of the present invention is to provide a blast furnace iron-making main ditch with a remote slag skimmer to solve the technical problems raised in the background technology; it is mainly used in the blast furnace ironmaking iron-making yard system, and is particularly suitable for situations where the site is limited and the extension of the iron-making main ditch is difficult during blast furnace expansion and overhaul. The present invention solves the problem of slag and iron separation in a limited space through a flexible segmented structure and slag skimmer arrangement.

[0007] In order to achieve the above object, the present invention provides the following technical solutions:

[0008] A blast furnace main ditch with a remote slag skimmer, the main ditch being arranged on a casthouse platform and comprising a main ditch section, a main ditch section, and a slag skimmer;

[0009] The main ditch section 1 and the main ditch section 2 are overlapped at a right angle or an obtuse angle to increase the total length of the main ditch for blast furnace iron tapping;

[0010] The skimmer is arranged at the end of the second section of the main ditch.

[0011] Furthermore, the first section of the main groove is designed to be straight, and the second section of the main groove is designed to be straight or curved.

[0012] Furthermore, at the overlap between the first main groove section and the second main groove section, the surface of the working layer of the second main groove section is higher than the surface of the working layer of the first main groove section.

[0013] Furthermore, the main trench section is provided with a downward slope along the iron flow direction, and the length of the main trench section is greater than or equal to 7m.

[0014] Furthermore, the second section of the main groove is provided with a downward slope along the flow direction of the iron flow.

[0015] Furthermore, the skimmer is used to separate slag and iron, with a lower opening for iron flow to pass through, and is connected to an iron branch ditch to discharge the iron flow;

[0016] The upper part is a solid structure to guide the slag flow, and a slag ditch is connected to the end of the second section of the main ditch to discharge the slag flow.

[0017] Furthermore, when the blast furnace is provided with two tapholes, the blast furnace tapping main ditch has two sets of parallel main ditch sections one and two main ditch sections, the ends of the two main ditch sections two can be set to the same skimmer, and the branch iron ditch connected behind the slag skimmer is set to 1 or 2.

[0018] Furthermore, a residual iron hole is provided at the end of the first section of the main ditch, the residual iron hole being connected to the residual iron ditch and being in a normally closed state and being opened only when the iron flow in the first section of the main ditch needs to be drained (e.g. when the main ditch needs overhaul).

[0019] The beneficial effects of the present invention are:

[0020] 1. The present invention's remote-mounted slag skimmer-type blast furnace tapping main ditch significantly improves the performance and adaptability of the blast furnace tapping system through its innovative segmented design and remote-mounted slag skimmer. Compared to the traditional main ditch design, the present invention flexibly extends the total length of the main ditch (up to 14 meters or more) by overlapping the main ditch section one with the main ditch section two at right angles or obtuse angles, and by designing the main ditch section two in a straight or curved shape. This effectively extends the slag-iron separation time, thereby improving the separation efficiency. This not only reduces the iron-in-slag phenomenon, reduces iron loss and safety hazards, but also optimizes the economic benefits of blast furnace tapping.

[0021] 2. The system design of the present invention is simple and efficient, with low investment cost and easy implementation. The height difference design of the working layer surface at the overlap between the main ditch section 1 and the main ditch section 2 (the working layer surface of the main ditch section 2 is higher than the working layer surface of the main ditch section 1) ensures that a small amount of molten iron remains in the main ditch section 1, reduces the impact of the slag jet on the ditch bottom, protects the refractory material and reduces maintenance costs. In addition, the two main ditches can share a slag skimmer and flexibly configure one or two branch iron ditches, which simplifies the system structure and reduces the equipment footprint. This design is particularly suitable for blast furnace expansion and renovation projects with limited space, facilitates rapid deployment, and reduces construction and renovation costs.

[0022] 3. This invention is highly adaptable to the modification of existing blast furnace tapping facilities and has a wide range of applications. Whether using a single or dual main trench system, the shape of the second main trench section and the position of the slag skimmer can be adjusted to flexibly adapt to different production requirements and site conditions. This technical solution not only improves slag-iron separation and equipment lifespan, but is also suitable for blast furnace production environments of all sizes.

[0023] Other advantages, objects, and features of the present invention will be described in part in the following description and, in part, will be apparent to those skilled in the art upon examination of the following description or may be learned from practice of the present invention. The objects and other advantages of the present invention may be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be described in detail below with reference to the accompanying drawings, in which:

[0025] Figure 1 This is a plan view of a main trough for a blast furnace with a remote slag skimmer according to an embodiment;

[0026] Figure 2 for Figure 1 AA cross-section diagram in.

[0027] Figure numbers: 1-main ditch section 1, 2-main ditch section 2, 3-residual iron ditch; 4-slag ditch; 5-slag skimmer, 6-branch iron ditch. DETAILED DESCRIPTION

[0028] The following describes the embodiments of the present invention by means of specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and the following embodiments and features in the embodiments can be combined with each other without conflict.

[0029] Among them, the accompanying drawings are only for illustrative purposes and represent only schematic diagrams rather than actual pictures, and should not be understood as limiting the present invention. In order to better illustrate the embodiments of the present invention, some parts of the accompanying drawings may be omitted, enlarged or reduced, and do not represent the dimensions of actual products. For those skilled in the art, it is understandable that some well-known structures and their descriptions may be omitted in the accompanying drawings.

[0030] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if there are terms such as "upper", "lower", "left", "right", "front", "back", etc. indicating directions or positional relationships, they are based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operate in a specific direction. Therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and cannot be understood as limiting the present invention. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0031] Example 1

[0032] like Figure 1 and Figure 2 As shown, this embodiment provides a blast furnace tapping ditch with a remote slag skimmer, suitable for use in scenarios where space is limited on the blast furnace tapping platform. The blast furnace tapping ditch consists of a first main ditch section 1, a second main ditch section 2, and a slag skimmer 5, which is used to effectively separate molten iron and slag.

[0033] Main trench section 1: Designed as a straight line, 8 meters in length, with width and depth adjusted to meet specific requirements (e.g., 1.0 meter in upper width, 0.7 meter in lower width, and 0.8 meter in depth). Main trench section 1 features a downward slope of 1% (adaptively adjusted to specific requirements) along the iron flow direction to ensure smooth flow of molten iron and slag. A residual iron hole is located at the end of main trench section 1, connected to residual iron trench 3, for draining residual iron during trench repair.

[0034] Main Trench Section 2: Designed as a curved section, it is 7 meters long, with width and depth adjusted to meet specific requirements (e.g., 1.0 meter upper width, 0.7 meter lower width, and 0.7 meter depth). Section 2 overlaps Main Trench Section 1 at a 90° angle to extend the overall length of the main trench and accommodate site constraints. At the overlap, the working surface of Section 2 is 0.4 meters higher than that of Section 1. (Because both Section 1 and Section 2 have downward slopes, and Section 2 also features a steep drop, the height difference at the overlap is greater than the depth difference between Sections 1 and 2.) This allows a small amount of molten iron to remain within Section 1, reducing the impact of the iron flow on the trench bottom and providing thermal insulation for the refractory materials. Section 2 also has a 1% downward slope in the direction of the iron flow.

[0035] Slag skimmer 5: Located at the end of the second main ditch section 2, it is used to separate slag and iron. The skimmer 5 has an opening at the bottom, through which the iron flows into the branch iron ditch 6 for discharge. The upper part is a solid structure that guides the molten slag to be discharged through the slag ditch 4 connected to the end of the second main ditch section 2.

[0036] In this embodiment, the combined length of the main trench section 1 and section 2 reaches 15 meters, matching the typical length of a traditional medium-sized blast furnace main trench, effectively improving slag and iron separation. The right-angle overlap design fully utilizes limited space and is suitable for site-constrained blast furnace renovation projects.

[0037] Example 2

[0038] like Figure 1 As shown, this embodiment provides a blast furnace iron-making main ditch suitable for a double main ditch system, which adopts two main ditch arranged in parallel and shares a slag skimmer 5 at the end to save space and improve operational flexibility.

[0039] Main Trench Section 1: Both main trench sections 1 are linear, 9 meters long, 1.6 meters wide at the top, 1.2 meters wide at the bottom, and 1.1 meters deep. Each section 1 has a downward slope of 1.5% along the iron flow direction to facilitate the flow of molten iron. A residual iron hole is located at the end of each main trench section 1 and connects to the residual iron ditch 3 to drain residual iron during trench repair.

[0040] Main Trench Section 2: The two Main Trench Sections 2 are designed as curved sections, with an upper width of 1.6 meters, a lower width of 1.2 meters, and a depth of 1 meter. Each Section 2 overlaps the corresponding Main Trench Section 1 at an obtuse 120° angle to accommodate the site layout and extend the overall length of the main trench. At the overlap, the working surface of Section 2 is 0.5 meters higher than that of Section 1, ensuring that molten iron is contained within Section 1, mitigating impacts and protecting the refractory material. Section 2 has a 1.5% downward slope along the direction of the iron flow.

[0041] Slag skimmer 5: The ends of the two main trench sections 2 share a common slag skimmer 5. The lower part of the slag skimmer 5 is provided with an opening, through which the iron flow flows into a common branch iron trench 6 for discharge; the upper part is a solid structure that guides the slag to the slag trench 4 for discharge.

[0042] In this embodiment, the total length of the two main trenches is 20 meters, which can reach the general length of the main trench of a traditional large blast furnace. By sharing a slag skimmer 5, not only the site space is saved, but also the operating efficiency of the dual main trench system is improved, which is suitable for the production needs of continuous iron casting in blast furnaces.

[0043] In another embodiment, two openings are provided at the lower portion of the skimmer 5 to connect the ends of the two main groove second sections 2 respectively, and allow the iron flows of the two main groove second sections 2 to flow into the two branch iron grooves 6 for discharge respectively.

[0044] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solutions, which should all be included in the scope of the claims of the present invention.

Claims

1. A blast furnace main ditch with a remote slag skimmer, characterized in that: The blast furnace main ditch is arranged on the iron-making platform, and the blast furnace main ditch includes a main ditch section 1, a main ditch section 2 and a slag skimmer; The main ditch section 1 and the main ditch section 2 are overlapped at a right angle or an obtuse angle to increase the total length of the main ditch for blast furnace iron tapping; The skimmer is arranged at the end of the second section of the main ditch.

2. The blast furnace iron tapping main ditch with remote slag skimmer according to claim 1, characterized in that: The first section of the main groove is designed to be straight, and the second section of the main groove is designed to be straight or curved.

3. The blast furnace iron tapping main ditch with remote slag skimmer according to claim 1, characterized in that: At the overlap of the main groove section 1 and the main groove section 2, the surface of the working layer of the main groove section 2 is higher than the surface of the working layer of the main groove section 1.

4. The blast furnace iron tapping main ditch with remote slag skimmer according to claim 1, characterized in that: The main trench section is provided with a downward slope along the iron flow direction, and the length of the main trench section is greater than or equal to 7m.

5. The blast furnace iron tapping main ditch with remote slag skimmer according to claim 1, characterized in that: The second section of the main ditch is provided with a downward slope along the flow direction of the iron flow.

6. The blast furnace iron tapping main ditch with remote slag skimmer according to claim 1, characterized in that: The skimmer is used to separate slag and iron, with a hole at the bottom for iron flow to pass through, and is connected to an iron branch ditch to discharge the iron flow; The upper part is a solid structure to guide the slag flow, and a slag ditch is connected to the end of the second section of the main ditch to discharge the slag flow.

7. The blast furnace iron tapping main ditch with remote slag skimmer according to claim 6, characterized in that: When the blast furnace is provided with two tapholes, the blast furnace tapping main ditch has two sets of parallel main ditch sections one and two main ditch sections, the ends of the two main ditch sections two are provided with the same skimmer, and the number of branch iron ditches connected to the skimmer is provided with one or two.

8. The blast furnace iron tapping main ditch with remote slag skimmer according to claim 1, characterized in that: A residual iron hole is provided at the end of one section of the main groove, and the residual iron hole is connected to the residual iron groove.

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