A layered and opposed type of submerged burner for steel ladle baking

Abstract

The utility model discloses a layered and opposite type sinking burner for ladle roasting, including gas pipeline, primary air casing, secondary air casing and tertiary air casing, the upper end of gas pipeline is used for with gas supply pipeline intercommunication and the lower end opening forms gas spout, the gap between primary air casing and gas pipeline forms primary air channel, the gap between secondary air casing and primary air casing forms secondary air channel, the gap between tertiary air casing and secondary air casing forms tertiary air channel, and primary air channel, secondary air channel and tertiary air channel are all used for with preheating combustion air pipeline intercommunication, and the lower end opening of primary air casing forms primary air spout, and the lower end opening of secondary air casing forms secondary air spout, and the lateral wall of tertiary air casing is equipped with a plurality of tertiary air spout. Can guarantee the full mixing of gas and combustion air, and can make full use of the heat of high temperature flue gas, and can carry out effective afterburning treatment to the unburnt component remaining in high temperature flue gas.

Description

Technical Field

[0001] This utility model belongs to the field of metallurgical equipment technology, specifically relating to a layered counter-impact sink burner for ladle baking. Background Technology

[0002] Ladle baking is an indispensable process in the iron and steel metallurgical production process. The purpose of baking is to remove moisture from the refractory lining of the ladle and preheat it to a suitable temperature. This prevents the refractory lining from peeling or even cracking due to the drastic temperature difference when the cold ladle comes into contact with high-temperature molten steel. Simultaneously, it reduces the temperature drop of the molten steel, ensuring the smooth progress of subsequent continuous casting or pouring processes. Ladle baking is achieved through a ladle baking device. Currently, the burners in traditional ladle baking devices have the following main technical shortcomings:

[0003] 1) The burners of traditional ladle baking devices mostly use single-layer or double-layer air distribution channels with relatively simple structures. The mixing of gas and combustion air is not sufficient, resulting in insufficient and unstable combustion of gas, which in turn affects thermal efficiency and the baking effect of the refractory lining of the ladle. It also directly leads to high gas consumption and large CO2 emissions per unit ladle baking operation.

[0004] 2) When using traditional ladle baking devices, the burners burn the gas, resulting in high-temperature flue gas that has a short residence time inside the ladle and is quickly discharged along the ladle wall. A large amount of heat is not effectively transferred to the refractory lining of the ladle, and the temperature difference between the top and bottom of the refractory lining can reach more than 100°C. The temperature uniformity of the refractory lining is poor, and unburned components such as CO remaining in the high-temperature flue gas due to incomplete combustion lack effective afterburning treatment and are directly emitted, which wastes energy and pollutes the environment.

[0005] 3) Traditional ladle baking devices generally lack effective means of flame length control for the burners, which can easily lead to the formation of local high-temperature zones, thereby increasing the burden of thermal NOx generation and environmental governance. Utility Model Content

[0006] In view of the above-mentioned defects of the prior art, the present invention provides a layered counter-current sink burner for ladle baking, which can ensure the full mixing of gas and combustion air, make full use of the heat of high-temperature flue gas, and effectively perform supplementary combustion treatment on unburned components such as CO remaining in high-temperature flue gas.

[0007] The technical solution adopted by this utility model to solve its technical problem is:

[0008] A layered counter-current submerged burner for ladle baking, the layered counter-current submerged burner being submerged inside the ladle and comprising, from the inside out, a gas pipeline, a primary air shell, a secondary air shell, and a tertiary air shell. The upper end of the gas pipeline extends above the primary air shell and is used to connect to a gas supply pipeline, and its lower end opens to form a gas nozzle. The gap between the primary air shell and the gas pipeline forms a primary air channel, the gap between the secondary air shell and the primary air shell forms a secondary air channel, and the gap between the tertiary air shell and the secondary air shell forms a tertiary air channel. The primary air channel, secondary air channel, and tertiary air channel are all used to connect to a preheating combustion air pipeline. The lower end opening of the primary air shell forms a primary air nozzle, the lower end opening of the secondary air shell forms a secondary air nozzle, and multiple tertiary air nozzles are provided on the side wall of the tertiary air shell.

[0009] Furthermore, the lower end of the gas pipeline is at a lower horizontal height than the lower end of the primary air casing, and the lower end of the secondary air casing is at a lower horizontal height than the lower end of the gas pipeline. The secondary air casing is provided with multiple swirl vanes, and the installation height of each swirl vane is higher than the lower end of the primary air casing.

[0010] Furthermore, both the gas pipeline and the primary air casing are vertically cylindrical, and the upper part of the secondary air casing is vertically cylindrical and the lower part is vertically inverted conical. The secondary air casing is divided into an upper secondary air casing cylindrical segment and a lower secondary air casing inverted conical segment. The lower end of the secondary air casing cylindrical segment is at a higher horizontal level than the lower end of the primary air casing, and multiple swirl blades are arranged at the lower end of the secondary air casing cylindrical segment.

[0011] Furthermore, the vertical axes of the gas pipeline, the primary air casing, and the secondary air casing coincide.

[0012] Furthermore, the multiple swirl blades have the same structure and are evenly distributed within the secondary air shell cylindrical segment.

[0013] Furthermore, the tertiary air housing includes an upper tertiary air housing first segment and a lower tertiary air housing second segment. Both the first and second segments of the tertiary air housing are vertically cylindrical, and the inner diameter of the second segment is larger than that of the first segment. The lower end of the second segment is at a higher horizontal level than the lower end of the secondary air housing cylindrical segment. A plurality of tertiary air nozzles are disposed on the vertical sidewall of the second segment of the tertiary air housing.

[0014] Furthermore, the vertical axes of the tertiary air shell, the secondary air shell, and the steel ladle coincide.

[0015] Furthermore, the aperture and installation height of the multiple tertiary air nozzles are the same and they are evenly distributed on the sidewall of the second section of the tertiary air housing.

[0016] Furthermore, the upper part of the gas pipeline is located above the primary air casing and is in the shape of a vertical inverted cone, while the lower part is in the shape of a vertical cylinder.

[0017] Furthermore, the upper ends of the primary air casing, the secondary air casing, and the tertiary air casing are flush.

[0018] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0019] This invention relates to a layered, counter-current submerged burner for ladle baking. The layered, counter-current submerged burner is submerged inside the ladle and includes a gas pipeline, a primary air shell, a secondary air shell, and a tertiary air shell arranged sequentially from the inside out. The upper end of the gas pipeline extends above the primary air shell and is used to connect with the gas supply pipeline, and the lower end opens to form a gas nozzle. The gap between the primary air shell and the gas pipeline forms a primary air channel, the gap between the secondary air shell and the primary air shell forms a secondary air channel, and the gap between the tertiary air shell and the secondary air shell forms a tertiary air channel. The primary air channel, the secondary air channel, and the tertiary air channel are all used to connect with the preheating combustion air pipeline. The lower end opening of the primary air shell forms a primary air nozzle, the lower end opening of the secondary air shell forms a secondary air nozzle, and multiple tertiary air nozzles are provided on the side wall of the tertiary air shell. Because this layered, counter-flow submerged burner has primary air channels, secondary air channels, and tertiary air channels sequentially arranged on the outside of the gas pipeline, this three-layer air distribution method ensures that the gas and preheated combustion air are mixed in a staged, orderly, and thorough manner. This results in more complete and stable combustion of the gas, thereby improving thermal efficiency and ensuring the baking effect of the refractory lining of the ladle. Furthermore, since this layered, counter-flow submerged burner is submerged inside the ladle, and multiple tertiary air nozzles are located on the side wall of the tertiary air shell, the preheated combustion air entering the tertiary air channels can be mixed with the gas after being ejected through these nozzles. The high-temperature flue gas moving upwards inside the ladle is forced to counteract, creating an upward and downward circulation of the flue gas within the ladle. This prolongs the residence time of the high-temperature flue gas inside the ladle, allowing the heat of the flue gas to be fully transferred to the refractory lining of the ladle. This controls the temperature difference between the upper and lower parts of the refractory lining within 50°C, significantly improving the temperature uniformity of the refractory lining. Furthermore, the preheated combustion air ejected through multiple tertiary air nozzles promotes the re-combustion of unburned components such as CO remaining in the high-temperature flue gas due to incomplete combustion, preventing energy waste and reducing CO emissions to minimize environmental pollution.

[0020] In this invention, because the lower end of the gas pipeline is at a lower horizontal height than the lower end of the primary air shell, the gas ejected downwards from the lower opening of the gas pipeline is completely surrounded by the preheated combustion air ejected downwards from the lower opening of the primary air shell. This allows a stable main flame to form and directly heat the refractory lining at the bottom of the ladle. Since the lower end of the secondary air shell is at a lower horizontal height than the lower end of the gas pipeline, and the secondary air shell contains multiple swirl vanes installed at a height higher than the lower end of the primary air shell, the preheated combustion air entering the secondary air channel forms a high-speed swirling turbulence after passing through the multiple swirl vanes, enveloping the main flame. This effectively extends the flame length, making the flame heat more evenly distributed along the vertical direction of the ladle and preventing the formation of localized high-temperature areas. This reduces the generation of thermal NOx at the source and alleviates the burden of environmental governance.

[0021] In summary, the layered counter-current submerged burner for ladle baking in this invention, through the synergistic effect of three-layer graded air distribution, swirling flame stabilization, and tertiary air counter-current combustion, can improve gas utilization while reducing gas consumption per unit ladle baking operation by more than 15%, and correspondingly reduce CO2 emissions by more than 15%, CO emission concentration by more than 30%, and NOx emission concentration by more than 20%. It significantly improves the baking quality of refractory linings for ladles while achieving significant energy-saving and environmental benefits. Attached Figure Description

[0022] Figure 1 This is a three-dimensional structural diagram of the layered counter-current submerged burner used for ladle baking in this utility model, showing its first direction.

[0023] Figure 2 This is a schematic diagram of the second-direction three-dimensional structure of the layered counter-current sinking burner used for ladle baking in this utility model.

[0024] Figure 3 This is a three-dimensional cross-sectional view of the layered counter-current submerged burner used for ladle baking in this utility model.

[0025] Figure 4 This is a schematic diagram before the preheated combustion air ejected from multiple tertiary air nozzles and the high-temperature flue gas moving upward inside the ladle are forcibly counteracted.

[0026] The following are the annotations in the figure: 101, gas pipeline; 102, primary air shell; 10301, secondary air shell cylindrical segment; 10302, secondary air shell inverted conical segment; 10401, tertiary air shell first segment; 10402, tertiary air shell second segment; 105, primary air duct; 106, secondary air duct; 107, tertiary air duct; 108, tertiary air nozzle; 109, swirl vane; 2, steel ladle. Detailed Implementation

[0027] The specific embodiments of this utility model will be further described in detail below with reference to the accompanying drawings. These embodiments are only used to illustrate this utility model and are not intended to limit it.

[0028] In the description of this utility model, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description. They 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 this utility model. In addition, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0029] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0030] Furthermore, in the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0031] like Figures 1-3As shown, a layered counter-current submerged burner for ladle baking is disclosed. The layered counter-current submerged burner is submerged inside the ladle 2 and includes a gas pipeline 101, a primary air shell 102, a secondary air shell, and a tertiary air shell arranged sequentially from the inside out. The upper end of the gas pipeline 101 extends above the primary air shell 102 and is used to connect with the gas supply pipeline, and the lower end opening forms a gas nozzle. The gap between the primary air shell 102 and the gas pipeline 101 forms a primary air channel 105. The gap between the secondary air shell and the primary air shell 102 forms a secondary air channel 106. The gap between the tertiary air shell and the secondary air shell forms a tertiary air channel 107. The primary air channel 105, the secondary air channel 106, and the tertiary air channel 107 are all used to connect with the preheating combustion air pipeline. The lower end opening of the primary air shell 102 forms a primary air nozzle, the lower end opening of the secondary air shell forms a secondary air nozzle, and multiple tertiary air nozzles 108 are provided on the side wall of the tertiary air shell.

[0032] Because the layered counter-current submerged burner has a primary air channel 105, a secondary air channel 106, and a tertiary air channel 107 sequentially arranged outside the gas pipeline 101, this three-layer air distribution method ensures that the gas and preheated combustion air are mixed in a graded, orderly, and thorough manner. This ensures more complete and stable combustion of the gas, thereby improving thermal efficiency and ensuring the baking effect of the refractory lining of the ladle 2. In addition, since the layered counter-current submerged burner is submerged inside the ladle 2, and multiple tertiary air nozzles 108 are arranged on the side wall of the tertiary air shell, the preheated combustion air entering the tertiary air channel 107 passes through the multiple tertiary air nozzles 108. After being ejected, the 08 nozzles forcefully counteract the high-temperature flue gas moving upward within the ladle 2, causing the high-temperature flue gas to form an upper and lower circulation within the ladle 2. This prolongs the residence time of the high-temperature flue gas within the ladle 2, allowing the heat of the high-temperature flue gas to be fully transferred to the refractory lining of the ladle 2. This controls the temperature difference between the upper and lower parts of the refractory lining of the ladle 2 to within 50°C, significantly improving the temperature uniformity of the refractory lining of the ladle 2. Furthermore, the preheated combustion air ejected through multiple tertiary air nozzles 108 promotes the re-combustion of unburned components such as CO remaining in the high-temperature flue gas due to incomplete combustion, preventing energy waste and reducing CO emissions to minimize environmental pollution.

[0033] In one embodiment, such as Figure 3 As shown, the lower end of the gas pipeline 101 is at a lower horizontal height than the lower end of the primary air housing 102, and the lower end of the secondary air housing is at a lower horizontal height than the lower end of the gas pipeline 101. The secondary air housing is provided with multiple swirl blades 109, and the installation height of each swirl blade 109 is higher than the lower end of the primary air housing 102.

[0034] Because the lower end of the gas pipeline 101 is at a lower horizontal height than the lower end of the primary air shell 102, the gas ejected downwards from the lower opening of the gas pipeline 101 is completely surrounded by the preheated combustion air ejected downwards from the lower opening of the primary air shell 102. This allows a stable main flame to form and directly heat the refractory lining at the bottom of the ladle 2. Because the lower end of the secondary air shell is at a lower horizontal height than the lower end of the gas pipeline 101, and the secondary air shell is equipped with multiple swirl vanes 109, each installed at a height higher than the lower end of the primary air shell 102, the preheated combustion air entering the secondary air channel 106 forms a high-speed swirling turbulent airflow after passing through the multiple swirl vanes 109, which envelops the main flame. This effectively extends the flame length, makes the flame heat more evenly distributed along the vertical direction of the ladle 2, and avoids the formation of local high-temperature areas, thereby reducing the generation of thermal NOx from the source and alleviating the burden of environmental governance.

[0035] Among them, such as Figure 3 As shown, the gas pipeline 101 and the primary air shell 102 are both vertical cylindrical shapes. The upper part of the secondary air shell is a vertical cylindrical shape and the lower part is a vertical inverted cone shape. The secondary air shell is divided into an upper secondary air shell cylindrical segment 10301 and a lower secondary air shell inverted cone segment 10302. The lower end of the secondary air shell cylindrical segment 10301 is at a higher horizontal height than the lower end of the primary air shell 102. Multiple swirl blades 109 are arranged at the lower end of the secondary air shell cylindrical segment 10301.

[0036] Since multiple swirl blades 109 are located at the lower end of the secondary air shell cylindrical section 10301, and the secondary air shell inverted cone section 10302 is located below the secondary air shell cylindrical section 10301, the high-speed swirling turbulent air formed by the preheated combustion air entering the secondary air channel 106 after passing through multiple swirl blades 109 will continue to enter the secondary air shell inverted cone section 10302 with gradually decreasing inner diameter. Therefore, the turbulent effect of the swirling turbulent air will be further enhanced, thereby more effectively extending the flame length.

[0037] In a first preferred embodiment, the vertical axes of the gas pipeline 101, the primary air shell 102, and the secondary air shell coincide; the multiple swirl blades 109 have the same structure and are evenly distributed within the cylindrical section 10301 of the secondary air shell.

[0038] This ensures the uniformity of the disturbance intensity of the resulting swirling turbulence.

[0039] In the second preferred embodiment, such as Figures 1-3As shown, the tertiary air casing includes a first tertiary air casing section 10401 at the top and a second tertiary air casing section 10402 at the bottom. Both the first tertiary air casing section 10401 and the second tertiary air casing section 10402 are vertical cylindrical in shape, and the inner diameter of the second tertiary air casing section 10402 is larger than the inner diameter of the first tertiary air casing section 10401. Furthermore, the lower end of the second tertiary air casing section 10402 is at a higher horizontal level than the lower end of the secondary air casing cylindrical section 10301. Multiple tertiary air nozzles 108 are disposed on the vertical sidewall of the second tertiary air casing section 10402.

[0040] Since multiple tertiary air nozzles 108 are located on the vertical sidewall of the second section 10402 of the tertiary air casing, the preheated combustion air entering the tertiary air passage 107 is ejected horizontally after passing through the multiple tertiary air nozzles 108, see... Figure 4 This creates a horizontal annular air curtain within the ladle 2, which effectively and forcefully counteracts the upward-moving high-temperature flue gas within the ladle 2. Figure 4 The diagram shown is a schematic diagram of the preheated combustion air ejected from multiple tertiary air nozzles 108 before it is forcibly counteracted by the high-temperature flue gas moving upward inside the ladle 2.

[0041] The vertical axes of the tertiary air shell, the secondary air shell, and the steel ladle 2 coincide; the aperture and installation height of the multiple tertiary air nozzles 108 are the same and they are evenly distributed on the side wall of the second section 10402 of the tertiary air shell.

[0042] This ensures that the preheated combustion air ejected horizontally from multiple tertiary air nozzles 108 is evenly distributed around the outer perimeter of the second section 10402 of the tertiary air shell. This, in turn, ensures the uniformity of the preheated combustion air concentration at various locations within the horizontal annular air curtain formed inside the ladle 2. This ensures that the force of the upward-moving high-temperature flue gas against the horizontal annular air curtain is consistent at various locations, thereby further ensuring that the heat from the high-temperature flue gas is evenly and fully transferred to the refractory lining of the ladle 2, thus guaranteeing the uniformity of the temperature field inside the ladle 2.

[0043] In the third preferred embodiment, such as Figure 3 As shown, the upper part of the gas pipeline 101 is above the primary air housing 102 and is in the shape of a vertical inverted cone, while the lower part is in the shape of a vertical cylinder.

[0044] In one embodiment, such as Figure 3 As shown, the upper ends of the primary air casing 102, the secondary air casing, and the tertiary air casing are flush.

[0045] Under typical operating conditions (ladle capacity approximately 150-300 tons, baking time approximately 2-3 hours, fuel gas either coke oven gas or natural gas), using this layered counter-current submerged burner for ladle baking can reduce fuel consumption by 15%-25% and CO2 emissions by 15%-25% per baking cycle compared to traditional single-layer or double-layer air distribution burners. The CO concentration in the flue gas is reduced from approximately 200-400 ppm in traditional devices to below 100 ppm, and the NOx concentration can be controlled below 80 mg / m³, demonstrating significant energy saving and emission reduction effects.

[0046] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present utility model, and these improvements and substitutions should also be considered within the protection scope of the present utility model.

Claims

1. A layered counter-current submerged burner for ladle baking, characterized in that: The layered counter-current submerged burner is used to submerge inside the ladle (2) and includes a gas pipeline (101), a primary air shell (102), a secondary air shell, and a tertiary air shell arranged sequentially from the inside out. The upper end of the gas pipeline (101) extends above the primary air shell (102) and is used to connect with the gas supply pipeline, and the lower end is open to form a gas nozzle. The gap between the primary air shell (102) and the gas pipeline (101) forms a primary air channel (105). The secondary air shell and the primary air shell (102) are connected to each other. The gap between the primary air duct (105), the secondary air duct (106), and the gap between the tertiary air duct and the secondary air duct form a tertiary air duct (107). The primary air duct (105), the secondary air duct (106), and the tertiary air duct (107) are all used to connect with the preheated combustion air pipeline. The lower opening of the primary air duct (102) forms a primary air nozzle, the lower opening of the secondary air duct forms a secondary air nozzle, and multiple tertiary air nozzles (108) are provided on the side wall of the tertiary air duct.

2. The layered counter-current sinking burner for ladle baking according to claim 1, characterized in that: The lower end of the gas pipeline (101) is at a lower horizontal height than the lower end of the primary air shell (102), and the lower end of the secondary air shell is at a lower horizontal height than the lower end of the gas pipeline (101). The secondary air shell is provided with a plurality of swirl vanes (109), and the installation height of each swirl vane (109) is higher than the lower end of the primary air shell (102).

3. A layered counter-current sinking burner for ladle baking according to claim 2, characterized in that: The gas pipeline (101) and the primary air shell (102) are both vertical cylindrical shapes. The upper part of the secondary air shell is a vertical cylindrical shape and the lower part is a vertical inverted cone shape. The secondary air shell is divided into an upper secondary air shell cylindrical segment (10301) and a lower secondary air shell inverted cone segment (10302). The lower end of the secondary air shell cylindrical segment (10301) is at a higher horizontal height than the lower end of the primary air shell (102). Multiple swirl blades (109) are arranged at the lower end of the secondary air shell cylindrical segment (10301).

4. A layered counter-current submerged burner for ladle baking according to claim 3, characterized in that: The vertical axes of the gas pipeline (101), the primary air casing (102), and the secondary air casing coincide.

5. A layered counter-current sinking burner for ladle baking according to claim 4, characterized in that: The multiple swirl blades (109) have the same structure and are evenly distributed within the secondary air shell cylindrical segment (10301).

6. A layered counter-current sinking burner for ladle baking according to claim 3, characterized in that: The tertiary air casing includes a first tertiary air casing section (10401) at the top and a second tertiary air casing section (10402) at the bottom. Both the first tertiary air casing section (10401) and the second tertiary air casing section (10402) are vertical cylindrical in shape. The inner diameter of the second tertiary air casing section (10402) is larger than the inner diameter of the first tertiary air casing section (10401), and the lower end of the second tertiary air casing section (10402) is at a higher horizontal level than the lower end of the secondary air casing cylindrical section (10301). A plurality of tertiary air nozzles (108) are disposed on the vertical sidewall of the second tertiary air casing section (10402).

7. A layered counter-current sinking burner for ladle baking according to claim 6, characterized in that: The vertical axes of the tertiary air shell, the secondary air shell, and the steel ladle (2) coincide.

8. A layered counter-current sinking burner for ladle baking according to claim 7, characterized in that: The multiple tertiary air nozzles (108) have the same aperture and installation height and are evenly distributed on the sidewall of the second section (10402) of the tertiary air housing.

9. A layered counter-current sinking burner for ladle baking according to claim 3, characterized in that: The upper part of the gas pipeline (101) is above the primary air casing (102) and is in the shape of a vertical inverted cone, while the lower part is in the shape of a vertical cylinder.

10. A layered counter-current sinking burner for ladle baking according to claim 1, characterized in that: The upper ends of the primary air casing (102), the secondary air casing, and the tertiary air casing are flush.

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