Group type bottom blowing device of small and medium-sized converter

Abstract

The invention relates to the technical field of converter steelmaking, in particular to a group type bottom blowing device for small and medium-sized converters. A circular ring area is defined on the bottom blowing component, and the circular ring area and the bottom blowing component are concentric; the diameter of the inner ring of the circular ring area is 0.3-0.4 time of the diameter of the bottom blowing component; the first hole group is formed in the bottom blowing part and is arranged in the inner ring; the diameter of the outer ring of the circular ring area is 0.6 time of the diameter of the bottom blowing component; and the second hole group is formed in the bottom blowing part and is arranged on the outer ring. According to the bottom blowing component, the circular ring area on the bottom blowing component is limited, the inner ring diameter and the outer ring diameter of the circular ring area are limited, and the specific positions of the inner ring and the outer ring are limited, so that a good stirring effect is achieved on a molten pool from the first hole group and the second hole group, the smelting efficiency of a converter is improved, energy loss is avoided, and energy waste is avoided.

Description

Technical Field

[0001] The invention relates to the technical field of converter steelmaking, and in particular to a group bottom blowing device for small and medium-sized converters. Background Art

[0002] Converter steelmaking technology is a revolutionary technology that plays an important role in smelting clean steel and low-carbon steel. The bottom blowing technology in the converter uses the turbulence of molten steel and gas to improve the reaction kinetic conditions of the converter, such as accelerating the reaction rate and promoting the rapid removal of phosphorus and carbon. Relevant research shows that the contribution rate of bottom blowing and top blowing to the kinetic energy of the molten pool is 9:1, which fully demonstrates that bottom blowing has a major influence on the stirring of the molten pool and plays a key role in the mixing effect of the molten pool.

[0003] At present, the converters in the prior art are divided into three specifications: large converters of more than 200 tons, medium-sized converters of 100 to 200 tons, and small converters of less than 100 tons. Among the three specifications of converters, small and medium-sized converters account for a large proportion in steel mills. However, the existing small and medium-sized converters are often equipped with single or double holes, and the stirring force of the single or double holes is obviously insufficient, and it is impossible to have a good stirring effect on the molten pool, resulting in a serious reduction in the smelting efficiency of the converter. If multiple holes are set at the bottom of the small and medium-sized converter, flow field interference will occur between the multiple holes during the stirring process, and energy loss will occur, resulting in energy waste.

[0004] To this end, the present application provides a group bottom blowing device for small and medium-sized converters. Summary of the invention

[0005] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a group bottom blowing device for small and medium-sized converters, thereby solving the problem that the stirring force of the converters with single or double holes in the prior art is obviously insufficient, and the molten pool cannot be stirred well, resulting in a serious reduction in the smelting efficiency of the converters. If multiple holes are set at the bottom of the small and medium-sized converters, flow field interference will occur between the multiple holes during the stirring process, and energy loss will occur, resulting in a technical problem of energy waste.

[0006] In order to achieve the above-mentioned purpose, the present invention provides a group bottom blowing device for small and medium-sized converters, comprising: a bottom blowing component; a circular ring area is defined on the bottom blowing component, and the circular ring area is concentric with the bottom blowing component; the inner ring diameter of the circular ring area is 0.3 times to 0.4 times the diameter of the bottom blowing component; a first hole group is opened in the bottom blowing component and arranged in the inner ring; the outer ring diameter of the circular ring area is 0.6 times the diameter of the bottom blowing component; a second hole group is opened in the bottom blowing component and arranged in the outer ring.

[0007] Optionally, the number of the first hole clusters is two, and the two first hole clusters are symmetrical with respect to the center of the bottom blowing component; the number of the second hole clusters is two, and the two second hole clusters are symmetrical with respect to the center of the bottom blowing component.

[0008] Optionally, the first hole cluster includes two first bottom blowing holes; and the second hole cluster includes two second bottom blowing holes.

[0009] Optionally, the diameters of the first bottom blowing hole and the second bottom blowing hole are both 70 mm to 90 mm.

[0010] Optionally, the diameters of the first bottom blowing hole and the second bottom blowing hole are the same.

[0011] Optionally, on the inner circle, the arc angle between the two first bottom blowing holes of the first hole group is 15°-30°; on the outer circle, the arc angle between the two second bottom blowing holes of the second hole group is 15°-30°.

[0012] Optionally, the arc angle between the two first bottom blowing holes is the same as the arc angle between the two second bottom blowing holes.

[0013] Optionally, the angle between the first hole cluster and the second hole cluster is ∠α, 0°≤∠α≤30°.

[0014] The beneficial effects of the present invention are:

[0015] The present invention provides a group bottom blowing device for a small and medium-sized converter, which defines the specific positions of the inner and outer rings by defining the annular area on the bottom blowing component and the inner and outer diameters of the annular area, and further defines the specific positions of the first hole group and the second hole group. This arrangement promotes the kinetic energy convergence between the bottom blowing streams, and the converged jets form a large circulation of the molten steel in the molten pool, improving the overall flow characteristics of the molten pool, so that the first hole group and the second hole group have a good stirring effect on the molten pool, improving the smelting efficiency of the converter, and no energy loss occurs, thus avoiding energy waste. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the arrangement of bottom blowing holes at the bottom of the converter in the prior art;

[0017] Figure 2 It is a schematic diagram of a group bottom blowing device for a small and medium-sized converter of the present invention;

[0018] Figure 3 Schematic diagram of bottom blowing hole arrangement of seven embodiments of the group bottom blowing device for small and medium-sized converters of the present invention;

[0019] Figure 4 Schematic diagram of molten pool velocity distribution of the prior art and seven embodiments of the present invention;

[0020] Figure 5 Schematic diagram of velocity distribution of a converter in the prior art and seven embodiments of the present invention at a height of 0.6 m from the liquid surface in the molten pool;

[0021] Figure 6 It is a schematic diagram of velocity distribution of a converter in the prior art and seven embodiments of the present invention at a height of 0.4 m from the liquid surface in the molten pool;

[0022] Figure 7 It is a schematic diagram of velocity distribution of a converter in the prior art and seven embodiments of the present invention at a height of 0.2 m from the liquid surface in the molten pool;

[0023] Figure 8 It is a proportional schematic diagram of the strong stirring zone of the present invention when the interval arc between the first pore group and the second pore group is 0°, 15°, and 30° respectively;

[0024] Fig. 9 It is a schematic diagram of the dead zone ratio in the molten pool, the average molten steel flow rate and the mixing time of the prior art converter and the seven embodiments of the present invention.

[0025] Description of reference numerals:

[0026] 1. Bottom blowing component; 2. Annular ring area; 3. Inner ring; 4. Outer ring; 5. First hole group; 6. First bottom blowing hole; 7. Second hole group; 8. Second bottom blowing hole. DETAILED DESCRIPTION

[0027] In order to better understand the above technical solution, exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a clearer and more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0028] There are 7 embodiments of the present invention, namely, Embodiment A, Embodiment B, Embodiment C, Embodiment D, Embodiment E, Embodiment F, and Embodiment G, where D represents the diameter of the bottom blowing component 1, wherein:

[0029] Embodiment A is as follows: the inner circle 3 of the first hole cluster 5 has a diameter of 0.3D, the outer circle 4 of the second hole cluster 7 has a diameter of 0.6D, the arc between the first hole cluster 5 and the second hole cluster 7 is 0°, the arc between the two first bottom blowing holes 6 is 15°, and the arc between the two second bottom blowing holes 8 is 15°.

[0030] Embodiment B is as follows: the inner circle 3 of the first hole cluster 5 has a diameter of 0.3D, the outer circle 4 of the second hole cluster 7 has a diameter of 0.6D, the arc interval between the first hole cluster 5 and the second hole cluster 7 is 15°, the arc interval between the two first bottom blowing holes 6 is 15°, and the arc interval between the two second bottom blowing holes 8 is 15°.

[0031] Embodiment C is as follows: the inner circle 3 of the first hole cluster 5 has a diameter of 0.3D, the outer circle 4 of the second hole cluster 7 has a diameter of 0.6D, the arc between the first hole cluster 5 and the second hole cluster 7 is 30°, the arc between the two first bottom blowing holes 6 is 15°, and the arc between the two second bottom blowing holes 8 is 15°.

[0032] Embodiment D is as follows: the inner circle 3 of the first hole cluster 5 has a diameter of 0.3D, the outer circle 4 of the second hole cluster 7 has a diameter of 0.6D, the arc of the interval between the first hole cluster 5 and the second hole cluster 7 is 0°, the arc of the interval between the two first bottom blowing holes 6 is 30°, and the arc of the interval between the two second bottom blowing holes 8 is 30°.

[0033] Embodiment E is as follows: the inner circle 3 of the first hole cluster 5 has a diameter of 0.4D, the outer circle 4 of the second hole cluster 7 has a diameter of 0.6D, the arc between the first hole cluster 5 and the second hole cluster 7 is 0°, the arc between the two first bottom blowing holes 6 is 15°, and the arc between the two second bottom blowing holes 8 is 15°.

[0034] Embodiment F is as follows: the inner circle 3 of the first hole cluster 5 has a diameter of 0.4D, the outer circle 4 of the second hole cluster 7 has a diameter of 0.6D, the arc between the first hole cluster 5 and the second hole cluster 7 is 15°, the arc between the two first bottom blowing holes 6 is 15°, and the arc between the two second bottom blowing holes 8 is 15°.

[0035] Embodiment G is as follows: the inner circle 3 of the first hole cluster 5 has a diameter of 0.4D, the outer circle 4 of the second hole cluster 7 has a diameter of 0.6D, the arc between the first hole cluster 5 and the second hole cluster 7 is 30°, the arc between the two first bottom blowing holes 6 is 15°, and the arc between the two second bottom blowing holes 8 is 15°.

[0036] The embodiment of the present invention provides a group bottom blowing device for a small and medium-sized converter, such as Figure 2 As shown, it includes: a bottom blowing component 1; a circular ring area 2 is defined on the bottom blowing component 1, and the circular ring area 2 is concentric with the bottom blowing component 1; the diameter of the inner ring 3 of the circular ring area 2 is 0.3 times to 0.4 times the diameter of the bottom blowing component 1; a first hole group 5 is opened in the bottom blowing component 1 and arranged in the inner ring 3; the diameter of the outer ring 4 of the circular ring area 2 is 0.6 times the diameter of the bottom blowing component 1; a second hole group 7 is opened in the bottom blowing component 1 and arranged in the outer ring 4.

[0037] For example, Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 and Figure 6As shown, since the distances between different hole clusters have obvious differences in the stirring effect on the molten steel in the molten pool, the first cluster of holes and the second cluster of holes in this embodiment are respectively arranged in the inner ring 3 and the outer ring 4 of the annular area 2. The positions of the inner ring 3 and the outer ring 4 in this embodiment are relatively moderate relative to the converter wall, the scouring of the wall by the jet is not obvious, and the kinetic energy of the jet is better absorbed by the molten steel, thereby improving the stirring effect on the molten pool.

[0038] from Figure 4 It can be seen that the gas ejected from the bottom blowing device of this embodiment forms a bottom blowing jet, which expands radially and entrains the surrounding molten steel to move. The molten steel moves upward from the bottom of the molten pool along with the bottom jet. In addition, the flow rate of the molten steel near the inlet of the bottom blowing device is significantly higher than that of other areas. When the molten steel approaches the surface of the molten pool, the molten steel turns to flow horizontally to both sides. When approaching the side furnace wall, the flow direction of the molten steel changes downward, forming a circulation pattern around the bottom blowing port. Figure 3 As shown, on the cross section shown in the figure, the prior art will produce four different circulation zones after bottom blowing in the converter, and the four different circulation zones are all located in the upper part of the molten pool, but the four different circulation zones are far away from each other. The direction of the flow of molten steel in the molten pool is relatively chaotic, and the circulation zone is closer to the jet, resulting in insufficient disturbance to the middle area, and the overall speed of the molten steel is slow. In the embodiments provided by the present invention, taking Example A as an example, on the same cross section as the prior art, four circulation zones are also formed. However, in Example A, there are two circulations located in the upper part of the molten pool, and the other two circulations are located outside the bottom blowing inlet, forming a complete cycle outside the inlet, so that the direction of the flow of molten steel in the molten pool flows according to the circulation trend law, and the circulation zone is far away from the jet, which increases the disturbance to the middle area, and finally increases the overall speed of the molten steel, enhancing the stirring effect of the molten steel in the converter.

[0039] For example, Figure 2 and Figure 3As shown, the first hole group 5 is arranged on the inner ring 3 of the annular area 2, and the second hole group 7 is arranged on the outer ring 4 of the annular area 2. When the diameter of the inner ring 3 is 0.3D and the diameter of the outer ring 4 is 0.6D, the distance between the first hole group 5 and the second hole group 7 is large, so that the stirring effect of the molten pool as a whole is better. At this time, the strong stirring area is relatively small, which is suitable for high flow conditions. When the diameter of the inner ring 3 is 0.4D and the diameter of the outer ring 4 is 0.6D, the first hole group 5 and the second hole group 7 are distributed more densely, then the stirring effect of the molten pool as a whole is weaker, but the strong stirring area is larger, which is suitable for low flow conditions. Taking Example A as an example, when the diameter of the inner ring 3 is 0.3D and the diameter of the outer ring 4 is 0.6D, the volume of the two circulation areas outside the jet generated by the bottom blowing device is large, so that the flow rate is relatively slow, but the scouring intensity on the furnace wall is low, and the circulation inside the jet is smaller and closer to the liquid surface, so that the collision between the two circulations leads to less energy loss.

[0040] For example, Figure 5 , Figure 6 and Figure 7 As shown in FIG. 1 , the speed distribution of the converter in the prior art and the seven embodiments of the present invention at different heights is shown. Figure 5 As shown in FIG. 1 , at 0.6 m below the molten pool surface, the dead zone distribution of the prior art is significantly larger than that of the seven embodiments of the present invention. The dead zone distribution of the prior art is relatively symmetrical, and the area with higher velocity is close to the bottom jet position, but the jets do not effectively coalesce, and the velocity distribution on the cross section is uneven. Figure 6 As shown in the figure, at 0.4m below the liquid surface, the flow velocity of each solution increases and the dead zone area decreases compared with that at 0.6m below the liquid surface. The movement behaviors of Example A, Example B and Example C at this depth are basically similar to those at 0.6m below the liquid surface, but the dead zone ratio of Example A and Example B is further reduced, and the low-speed area in the center almost disappears. Figure 7 As shown in the figure, at a depth of 0.2m below the liquid surface, the bottom blowing jet is fully developed, transitioning from the initial vertical flow to the lateral flow. This change significantly increases the flow rate of each section, and the dead zone area is reduced compared with the section at 0.6m below the liquid surface. The reason for this phenomenon is that the bubbles near the surface of the molten pool burst, which improves the fluidity of the molten steel and reduces the dead zone, which is conducive to improving steelmaking efficiency and better controlling the composition during the steelmaking process.

[0041] like Fig. 9 As shown, the dead zone ratios in the lower molten pool of the prior art converter and the seven embodiments of the present invention. Fig. 9It can be clearly seen that there is a difference in the dead zone ratio between the prior art converter and the 7 embodiments of the present invention. Specifically, the dead zone ratio of embodiment A and embodiment E is the smallest, and the dead zone ratio of embodiment C and embodiment G is the largest. This observation is positively correlated with the strong stirring zone ratio, indicating that the size of the strong stirring zone in the molten pool effectively affects the dead zone ratio. It is worth noting that embodiment A shows the lowest dead zone ratio in the molten pool. This result is due to the fact that in embodiment A, the inner circle 3 of the first hole group 5 is arranged with a diameter of 0.3D, the outer circle 4 of the second hole group 7 is arranged with a diameter of 0.6D, and the interval arc between the first hole group 5 and the second hole group 7 is 0°. Therefore, the energy loss caused between the first hole group 5 and the second hole group 7 is small, and the distance from the furnace wall is optimal. Therefore, the kinetic energy of the bottom blowing jet is fully utilized in the molten pool, thereby enhancing the stirring of the molten steel. In addition, in embodiment A, the dead zone ratio in the molten pool is very low, only 0.6%. This means that reducing the distance between bottom blowing jet hole clusters can effectively reduce the dead zone ratio. Too long a distance between bottom blowing jet hole clusters will increase the dead zone ratio in the molten pool of a medium-sized converter, thereby hindering the stirring efficiency.

[0042] In a possible embodiment, Figure 2 and Figure 3 As shown, there are two first hole clusters 5 , which are symmetrical with respect to the center of the bottom blowing component 1 ; there are two second hole clusters 7 , which are symmetrical with respect to the center of the bottom blowing component 1 .

[0043] Exemplarily, in this embodiment, the first hole cluster 5 and the second hole cluster 7 are arranged symmetrically relative to the center of the bottom blowing component 1. This arrangement effectively balances the kinetic energy input of the bottom blowing jets on both sides of the molten pool, reduces the number and size of small circulation areas in the molten pool, and improves energy efficiency. In addition, due to the central symmetry, the movement directions of the jets are less likely to conflict, and the large circulation formed by the flow stream driving the molten steel is more conducive to stirring the entire molten pool.

[0044] In a possible embodiment, Figure 2 and Figure 3 As shown, the first hole cluster 5 includes two first bottom blowing holes 6 ; the second hole cluster 7 includes two second bottom blowing holes 8 .

[0045] Exemplarily, taking the first hole cluster 5 as an example, compared with the single-hole bottom blowing hole in the prior art, the first hole cluster 5 of this embodiment includes two first bottom blowing holes 6, and the distance between the two first bottom blowing holes 6 is closer. The two first bottom blowing holes 6 form a hole cluster, "grouped in pairs". This arrangement makes the bottom blowing jet distribution more concentrated, and the jets are more likely to merge, which increases the kinetic energy of the flow, thereby increasing the stirring ability of the bottom blowing device for the molten steel.

[0046] The situation of the second hole group 7 in this embodiment is similar to that of the first hole group 5 and will not be described again here.

[0047] In a possible embodiment, Figure 2 and Figure 3 As shown, the diameters of the first bottom blowing hole 6 and the second bottom blowing hole 8 are both 70 mm to 90 mm.

[0048] In a possible embodiment, Figure 2 and Figure 3 As shown, the diameters of the first bottom blowing hole 6 and the second bottom blowing hole 8 are the same.

[0049] Exemplarily, the diameters of the first bottom blowing holes 6 and the second bottom blowing holes 8 provided in the present embodiment are moderate. When matched with existing small and medium-sized converters, the first bottom blowing holes 6 and the second bottom blowing holes 8 in the present example can, on the one hand, effectively save bottom blowing gas. On the other hand, the diameter range of the present embodiment can effectively improve the stirring effect of the molten pool.

[0050] In a possible embodiment, Figure 2 and Figure 3 As shown, on the inner circle 3, the arc between the two first bottom blowing holes 6 of the first hole group 5 is 15°-30°; on the outer circle 4, the arc between the two second bottom blowing holes 8 of the second hole group 7 is 15°-30°.

[0051] For example, Figure 4 and Figure 5 As shown, taking the first hole group 5 as an example, the arc of the interval between the two first bottom blowing holes 6 in the first hole group 5 directly affects the distance between the two first bottom blowing holes 6, as well as the diameter size of the two first bottom blowing holes 6. The smaller the arc of the interval between the two first bottom blowing holes 6, the better the gathering effect of the bottom blowing streams, but the smaller the range of the streams affected; if the arc of the interval between the two first bottom blowing holes 6 is larger, the more small circulation areas are formed by the streams, but the energy loss is greater. Therefore, this embodiment sets the arc of the interval between the two first bottom blowing holes 6 of the first hole group 5 to 15°-30°, which not only ensures the better gathering effect of the bottom blowing streams, but also takes into account the number of circulation areas, and does not cause energy loss.

[0052] The situation of the second hole group 7 in this embodiment is similar to that of the first hole group 5 and will not be described again here.

[0053] In a possible embodiment, Figure 2 and Figure 3 As shown, the arc distance between the two first bottom blowing holes 6 is the same as the arc distance between the two second bottom blowing holes 8 .

[0054] For example, since the arc of the interval between the two first bottom blowing holes 6 directly affects the distance between the two first bottom blowing holes 6, and thus affects the gathering effect of the bottom blowing streams. When the arc of the interval between the two first bottom blowing holes 6 is the same as the arc of the interval between the two second bottom blowing holes 8, the energy of the bottom blowing streams generated by the first bottom blowing holes 6 and the bottom blowing streams generated by the second bottom blowing holes 8 is the same, so the gathering effect of the two bottom blowing streams is the best, and the gathering deviation will not be caused by the different energy of the two bottom blowing streams.

[0055] In a possible embodiment, Figure 2 and Figure 3 As shown, the angle between the first hole group 5 and the second hole group 7 is ∠α, 0°≤∠α≤30°.

[0056] Exemplarily, the smaller the angle between the first hole cluster 5 and the second hole cluster 7, that is, when ∠α is close to 0°, the better the stirring effect on the molten pool. This is because the smaller the angle between the first hole cluster 5 and the second hole cluster 7, the more conducive it is to the fusion between the stirring zones formed by the bottom blowing jet, thereby improving the energy utilization efficiency and promoting the generation of large-scale circulation in the molten pool. On the contrary, when the angle between the first hole cluster 5 and the second hole cluster 7 is 30°, the distance between the first hole cluster 5 and the second hole cluster 7 increases, and a new stirring zone can be formed when the bottom blowing jet rises. If the angle between the first hole cluster 5 and the second hole cluster 7 continues to be larger, these stirring zones will collide and cannot be effectively merged, resulting in energy loss, thereby reducing the energy utilization efficiency of the molten pool. Therefore, in this embodiment, the angle between the first hole cluster 5 and the second hole cluster 7 is ∠α, 0°≤∠α≤30°, thereby taking into account the fusion between the stirring zones formed by the bottom blowing jet, and avoiding the energy loss caused by the collision of the newly formed stirring zones, thereby improving the energy utilization of the molten pool. Fig. 9 As shown, the smaller the angle between the first hole cluster 5 and the second hole cluster 7 is, the smaller the dead zone is. The difference between the dead zones of 0° and 15° is very small, but if the angle between the first hole cluster 5 and the second hole cluster 7 exceeds 30°, the dead zone ratio will be greatly increased, and a dead zone will be formed between the jets. The excessively large angle between the first hole cluster 5 and the second hole cluster 7 has an adverse effect on the circulation of the molten pool, and the disturbance between the streams is too large, which reduces the stirring effect.

[0057] This example also compares the proportion of the strong stirring area. The results show that:

[0058] When the interval arc between the first pore cluster 5 and the second pore cluster 7 is 0°, the proportion of the strong stirring zone in Embodiment A and Embodiment E is the largest.

[0059] like Figure 8As shown in the figure, when the interval arc between the first hole cluster 5 and the second hole cluster 7 is 15°, the proportion of embodiment B and embodiment F is slightly smaller, while the proportion of embodiment C and embodiment G with a small group angle of 30° is the smallest, which also shows that when the angle between the hole clusters is too large, it is not conducive to enhancing the stirring of the molten pool. Therefore, reducing the angle of the hole clusters in the arrangement can significantly increase the proportion of the strong stirring zone in the molten pool. This is because the angle between the clusters is small, which is conducive to the fusion between the stirring zones formed by the bottom blowing jet, thereby improving the energy utilization efficiency and promoting the generation of large-scale circulation in the molten pool.

[0060] When the interval arc between the first hole cluster 5 and the second hole cluster 7 is 30°, the increase in the distance between the hole clusters leads to the formation of a new stirring zone when the bottom blowing jet rises. However, due to the large angle, these stirring zones collide and cannot be effectively merged, resulting in a certain amount of energy loss, thereby reducing the energy utilization efficiency of the molten pool.

[0061] The mixing time and average molten steel flow rate of the molten pool in the prior art converter and the seven embodiments of the present invention. Fig. 9 As shown, after the molten steel reaches a stable state, a tracer simulation is performed to simulate the mass transfer in the molten steel. The results show that the mixing time of Example A is slightly shorter than that of Example E. Among them, the interval arc between the first hole group 5 and the second hole group 7 of Example A is 0°, and the mixing time is the shortest. This is because the interval arc between the first hole group 5 and the second hole group 7 affects the size of the small circulation area between the bottom blowing jets. The larger the volume of the small circulation area, the more obvious the kinetic energy loss between each other, and the greater the impact on the large circulation of the molten pool. On the contrary, when the interval arc between the first hole group 5 and the second hole group 7 is 30°, the mixing time increases by 30% compared with 15°, that is, the mixing time of Example D increases by 30% compared with Example A. It can be seen that a large interval arc between the first hole group 5 and the second hole group 7 will cause energy loss, thereby affecting the bottom blowing effect.

[0062] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0063] In the present invention, unless otherwise clearly specified and limited, when a first feature is “on” or “below” a second feature, it may be that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, when a first feature is “above”, “above” or “above” a second feature, it may be that the first feature is directly above or obliquely above the second feature, or it may simply mean that the first feature is higher in level than the second feature. When a first feature is “below”, “below” or “below” a second feature, it may be that the first feature is directly below or obliquely below the second feature, or it may simply mean that the first feature is lower in level than the second feature.

[0064] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may alter, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A group bottom blowing device for small and medium-sized converters, characterized in that: include: Bottom blowing parts; The bottom blowing component is defined with an annular area, and the annular area is concentric with the bottom blowing component; The inner diameter of the annular zone is 0.3 to 0.4 times the diameter of the bottom blowing component; A first hole group is provided in the bottom blowing component and arranged in the inner ring; The outer diameter of the annular zone is 0.6 times the diameter of the bottom blowing component; The second hole group is opened in the bottom blowing component and is arranged on the outer ring.

2. The group bottom blowing device for small and medium-sized converters according to claim 1, characterized in that: The number of the first hole clusters is two, and the two first hole clusters are symmetrical with respect to the center of the bottom blowing component; The number of the second hole clusters is two, and the two second hole clusters are symmetrical with respect to the center of the bottom blowing component.

3. The group bottom blowing device for small and medium-sized converters according to claim 2, characterized in that: The first hole cluster includes two first bottom blowing holes; The second hole cluster includes two second bottom blowing holes.

4. The group bottom blowing device for small and medium-sized converters according to claim 3, characterized in that: The diameters of the first bottom blowing hole and the second bottom blowing hole are both 70 mm to 90 mm.

5. The group bottom blowing device for small and medium-sized converters according to claim 4, characterized in that: The first bottom blowing hole and the second bottom blowing hole have the same diameter.

6. The group bottom blowing device for a small and medium-sized converter according to claim 3, characterized in that: On the inner ring, the arc between the two first bottom blowing holes of the first hole group is 15°-30°; On the outer ring, the arc angle between the two second bottom blowing holes of the second hole group is 15°-30°.

7. The group bottom blowing device for a small and medium-sized converter according to claim 6, characterized in that: The arc angle between the two first bottom blowing holes is the same as the arc angle between the two second bottom blowing holes.

8. The group bottom blowing device for a small and medium-sized converter according to claim 1, characterized in that: The angle between the first hole group and the second hole group is ∠α, and 0°≤∠α≤30°.

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