Converter blowing system

Abstract

The utility model relates to a converter blowing system which comprises a blowing oxygen lance, the blowing oxygen lance is connected with an oxygen header pipe, a carbon dioxide header pipe is connected beside the oxygen header pipe, and the carbon dioxide header pipe is connected with a carbon dioxide supply mechanism. The carbon dioxide supply mechanism comprises a carbon dioxide storage unit, a hot-blast stove and a hot-blast stove flue gas pipe connected to the hot-blast stove, a pressurizing machine and a purification unit are sequentially arranged on the hot-blast stove flue gas pipe, and a carbon dioxide outlet of the purification unit is communicated with a carbon dioxide inlet of the carbon dioxide storage unit; the carbon dioxide header pipe is connected with a carbon dioxide outlet of the carbon dioxide storage unit. According to the utility model, the carbon dioxide is prepared by utilizing the flue gas of the hot-blast stove, so that the carbon dioxide preparation efficiency can be effectively ensured, the obtained carbon dioxide is high in quality, and the carbon dioxide preparation cost is reduced; the flue gas of the hot blast stove is supplied to the blowing oxygen lance after being pressurized and purified, the purity is high, the cooling effect can be guaranteed, control over the adding amount is more accurate, and meanwhile pollution to molten steel can be reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of converter production, and in particular relates to a converter blowing system. Background Art

[0002] The converter steelmaking process requires no external energy, and its own chemical reactions generate excess heat. Therefore, an appropriate amount of coolant must be added to accurately hit the endpoint temperature. Commonly used coolants include scrap steel, pig iron, iron ore, iron oxide scale, pellets, sintered ore, limestone, and raw dolomite. Scrap steel, pig iron, and iron ore offer relatively good cooling effects. Using these solid coolants is more expensive and can easily introduce impurities such as S, P, and Si, affecting the quality of the molten steel. A small number of steel companies use CO2 gas as a coolant, replacing solid coolants like iron ore and iron oxide scale. However, CO2 gas is not a commonly used raw material in steelmaking, and its production alone requires considerable energy. Utility Model Content

[0003] The utility model relates to a converter blowing system, which can at least solve some defects of the prior art.

[0004] The utility model relates to a converter blowing system, comprising a blowing oxygen lance, wherein the blowing oxygen lance is connected to an oxygen main pipe, a carbon dioxide main pipe is connected to the oxygen main pipe, and the carbon dioxide main pipe is connected to a carbon dioxide supply mechanism, wherein the carbon dioxide supply mechanism comprises a carbon dioxide storage unit, a hot blast furnace and a hot blast furnace flue gas pipe connected to the hot blast furnace, a pressurizing machine and a purification unit are sequentially arranged on the hot blast furnace flue gas pipe, a carbon dioxide outlet of the purification unit is communicated with a carbon dioxide inlet of the carbon dioxide storage unit, and the carbon dioxide main pipe is connected to the carbon dioxide outlet of the carbon dioxide storage unit.

[0005] As one of the embodiments, the purification unit includes a pressure swing adsorption device and a liquefaction purification device, the pressure swing adsorption device is configured with a carbon dioxide adsorbent, the hot blast furnace flue gas pipe is connected to the flue gas inlet of the pressure swing adsorption device, the carbon dioxide delivery pipe of the pressure swing adsorption device is connected to the carbon dioxide inlet of the liquefaction purification device, and the carbon dioxide delivery pipe of the liquefaction purification device is connected to the carbon dioxide storage unit.

[0006] As one of the embodiments, the carbon dioxide storage unit is a liquefied gas storage tank for storing liquid carbon dioxide, and a carbon dioxide gasification unit is provided on the inlet side of the carbon dioxide main pipe; alternatively, the carbon dioxide storage unit is a gas storage cabinet for storing gaseous carbon dioxide, and a carbon dioxide gasification unit is provided on the carbon dioxide delivery pipe of the liquefaction and purification device.

[0007] As one of the implementation modes, the fuel inlet of the hot blast stove is connected to a converter gas pipe and / or a blast furnace gas pipe.

[0008] As one of the implementation modes, a main pipe valve control unit is arranged on the carbon dioxide main pipe, and the main pipe valve control unit at least includes a pressure regulating valve and a shut-off valve.

[0009] As one of the implementation modes, the manifold valve control unit further includes a flow regulating valve and a flow meter interlocked with the flow regulating valve, and the flow regulating valve and the flow meter are arranged downstream of the pressure regulating valve.

[0010] As one of the implementation methods, there are two oxygen main pipes, and the outlet end of the carbon dioxide main pipe is connected to two carbon dioxide branch pipes, which are respectively connected to the two oxygen main pipes, and branch pipe valve control units are respectively provided on the two carbon dioxide main pipes.

[0011] As one of the implementation modes, the branch pipe valve control unit includes a stop valve, a quick-cut valve and a check valve sequentially arranged along the flow direction of carbon dioxide.

[0012] As one of the implementation modes, the oxygen main pipe is also connected to a nitrogen main pipe.

[0013] As one of the implementation modes, the converter blowing system is further equipped with an oxygen lance valve chamber, the oxygen main pipe and the carbon dioxide main pipe are both arranged in the oxygen lance valve chamber, and the pipe inlet and the pipe outlet both extend out of the oxygen lance valve chamber.

[0014] The utility model has at least the following beneficial effects:

[0015] In this utility model, carbon dioxide is produced from hot blast furnace flue gas. As a by-product of steel mills, hot blast furnace flue gas has a high carbon dioxide concentration, which effectively ensures carbon dioxide production efficiency and high-quality carbon dioxide, reduces carbon dioxide production costs, and reduces the greenhouse effect caused by hot blast furnace flue gas emissions. After being pressurized and purified, the hot blast furnace flue gas is supplied to the blowing oxygen lance, achieving high purity and ensuring cooling efficiency. The addition amount can be more precisely controlled, while also reducing contamination of molten steel. In addition, the chemical reaction product of CO2 gas used as a coolant is CO. The high-purity carbon dioxide can effectively improve the quality of converter gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0017] Figure 1 This is a structural schematic diagram of a converter blowing system provided in an embodiment of the present utility model. DETAILED DESCRIPTION

[0018] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0019] like Figure 1 An embodiment of the utility model provides a converter blowing system, comprising a blowing oxygen lance 1, wherein the blowing oxygen lance 1 is connected to an oxygen main pipe 2, a carbon dioxide main pipe 3 is connected to the oxygen main pipe 2, and the carbon dioxide main pipe 3 is connected to a carbon dioxide supply mechanism, wherein the carbon dioxide supply mechanism comprises a carbon dioxide storage unit 55, a hot blast furnace 51 and a hot blast furnace flue gas pipe connected to the hot blast furnace 51, a compressor 52 and a purification unit are sequentially arranged on the hot blast furnace flue gas pipe, a carbon dioxide outlet of the purification unit is connected to the carbon dioxide inlet of the carbon dioxide storage unit 55, and the carbon dioxide main pipe 3 is connected to the carbon dioxide outlet of the carbon dioxide storage unit 55.

[0020] In this embodiment, the carbon dioxide main pipe 3 is connected to the oxygen main pipe 2, so the blowing oxygen lance 1 can be used to add carbon dioxide gas into the converter without the need for an additional carbon dioxide spray gun.

[0021] An oxygen control valve group is arranged on the oxygen main pipe 2, and the bypass point of the carbon dioxide main pipe 3 can be located downstream of the oxygen control valve group.

[0022] Preferably, a manifold valve control unit is disposed on the carbon dioxide main pipe 3. Through the coordination of the manifold valve control unit and the oxygen control valve group, the oxygen blowing lance 1 can freely switch between oxygen blowing mode, carbon dioxide blowing mode, or mixed blowing mode. In one embodiment, the converter blowing system is further configured with an oxygen lance valve chamber, wherein the oxygen main pipe 2 and the carbon dioxide main pipe 3 are both disposed within the oxygen lance valve chamber, with the pipe inlet and pipe outlet both extending outside the oxygen lance valve chamber. The oxygen control valve group and the manifold valve control unit are both located within the oxygen lance valve chamber, facilitating management and maintenance.

[0023] Preferably, if Figure 1The main pipe valve control unit includes at least a pressure regulating valve 34 and a stop valve 31. The stop valve 31 can control the on and off of the carbon dioxide main pipe 3, and the pressure regulating valve 34 can adjust the carbon dioxide pressure on the outlet side of the carbon dioxide main pipe 3 to ensure that the carbon dioxide gas is added to the converter smoothly and accurately. For example, the carbon dioxide gas pressure can be made slightly higher than the oxygen pressure so that the carbon dioxide gas can be mixed with the oxygen.

[0024] Furthermore, if Figure 1 The main valve control unit also includes a flow regulating valve 36 and a flow meter 35 interlocked with the flow regulating valve 36. The flow regulating valve 36 and the flow meter 35 are arranged downstream of the pressure regulating valve 34. The flow meter 35 and the flow regulating valve 36 can realize automatic control of the carbon dioxide flow, especially the precise control of the amount of carbon dioxide added as the temperature of the molten steel changes.

[0025] Furthermore, if Figure 1 The main valve control unit also includes a quick-cut valve 33, which can quickly cut off the supply of carbon dioxide in the event of an accident such as an oxygen lance accident.

[0026] Alternatively, as Figure 1 A filter 32 is also provided on the carbon dioxide main pipe 3 to improve the cleanliness of the carbon dioxide gas, ensure the reliability of the carbon dioxide supply and reduce the pollution to the quality of the molten steel.

[0027] In one embodiment, Figure 1 There are two oxygen main pipes 2, and the outlet end of the carbon dioxide main pipe 3 is connected to two carbon dioxide branch pipes 30. The two carbon dioxide branch pipes 30 are respectively connected to the two oxygen main pipes 2. The two carbon dioxide main pipes 3 are respectively provided with branch pipe valve control units. The two oxygen main pipes 2 are used and the other is used as a backup, which can improve the working reliability and production safety of the converter refining system. Optionally, Figure 1 The branch pipe valve control unit includes a stop valve 301, a quick-cut valve 302 and a check valve 303 arranged in sequence along the flow direction of carbon dioxide.

[0028] In one embodiment, Figure 1 The oxygen main pipe 2 is also connected to a nitrogen main pipe 4, so that the blowing oxygen lance 1 can also spray nitrogen, including but not limited to performing slag splashing and furnace protection operations; when there are two oxygen main pipes 2, the nitrogen main pipe 4 is correspondingly configured as two, which are respectively connected to the two oxygen main pipes 2.

[0029] In this embodiment, hot blast furnace flue gas is used to produce carbon dioxide. As a by-product of steel mills, hot blast furnace flue gas has a high carbon dioxide concentration, which effectively ensures carbon dioxide production efficiency and high-quality carbon dioxide, reduces carbon dioxide production costs, and reduces the greenhouse effect caused by hot blast furnace flue gas emissions. After being pressurized and purified, the hot blast furnace flue gas is supplied to the blowing oxygen lance 1. Its high purity ensures effective cooling, allows for more precise control of the added oxygen amount, and reduces contamination of the molten steel. Furthermore, the chemical reaction product of CO2 gas used as a coolant is CO. High-purity carbon dioxide can effectively improve the quality of converter gas.

[0030] In one embodiment, the purification unit includes a pressure swing adsorption device 53 and a liquefaction purification device 54. The pressure swing adsorption device 53 is equipped with a carbon dioxide adsorbent. The hot blast furnace flue gas pipe is connected to the flue gas inlet of the pressure swing adsorption device 53. The carbon dioxide delivery pipe of the pressure swing adsorption device 53 is connected to the carbon dioxide inlet of the liquefaction purification device 54. The carbon dioxide delivery pipe of the liquefaction purification device 54 is connected to the carbon dioxide storage unit 55. In this embodiment, a pressure swing adsorption purification method combined with cooling and liquefaction purification is adopted, which has high process maturity, easily controllable purification costs, and can produce high-purity carbon dioxide. Generally, the purity of carbon dioxide obtained by the pressure swing adsorption device 53 can reach 95%, and the purity of carbon dioxide obtained by the liquefaction purification device 54 can reach 99.9%. Of course, the purity of the pressure swing adsorption purification and cooling and liquefaction purification can be flexibly controlled according to actual operating conditions.

[0031] When the carbon dioxide is stored in a liquid state, the carbon dioxide storage unit 55 may be a liquefied gas storage tank; preferably, a carbon dioxide vaporization unit is provided at the inlet side of the carbon dioxide main pipe 3. When the carbon dioxide is stored in a gaseous state, the carbon dioxide storage unit 55 may be a gas storage cabinet. In this case, a carbon dioxide vaporization unit may be provided on the carbon dioxide delivery pipe of the liquefaction and purification device 54.

[0032] Preferably, the fuel inlet of the hot blast furnace 51 is connected to a converter gas pipe and / or a blast furnace gas pipe. Using steel mill byproducts as fuel for the hot blast furnace 51 can reduce production costs. Furthermore, using converter gas / blast furnace gas as fuel ensures a relatively high carbon dioxide concentration in the hot blast furnace flue gas, thereby facilitating subsequent carbon dioxide purification operations. For example, when the hot blast furnace 51 uses blast furnace gas (CO content 25.5%, CO2 content 14.5%) as fuel and the excess air coefficient is selected to be 1.1, the CO2 content in the hot blast furnace flue gas can be as high as 25%. When the hot blast furnace 51 uses converter gas (CO content 59%, CO2 content 18.5%) as fuel and the excess air coefficient is selected to be 1.1, the CO2 content in the hot blast furnace flue gas can be as high as 34%.

[0033] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A converter blowing system comprising a blowing oxygen lance connected to an oxygen main, characterized in that: A carbon dioxide main pipe is connected to the oxygen main pipe, and the carbon dioxide main pipe is connected to a carbon dioxide supply mechanism. The carbon dioxide supply mechanism includes a carbon dioxide storage unit, a hot blast furnace and a hot blast furnace flue gas pipe connected to the hot blast furnace. A compressor and a purification unit are arranged in sequence on the hot blast furnace flue gas pipe. The carbon dioxide outlet of the purification unit is connected to the carbon dioxide inlet of the carbon dioxide storage unit, and the carbon dioxide main pipe is connected to the carbon dioxide outlet of the carbon dioxide storage unit.

2. The converter blowing system according to claim 1, wherein: The purification unit includes a pressure swing adsorption device and a liquefaction purification device. The pressure swing adsorption device is equipped with a carbon dioxide adsorbent. The hot blast furnace flue gas pipe is connected to the flue gas inlet of the pressure swing adsorption device. The carbon dioxide delivery pipe of the pressure swing adsorption device is connected to the carbon dioxide inlet of the liquefaction purification device. The carbon dioxide delivery pipe of the liquefaction purification device is connected to the carbon dioxide storage unit.

3. The converter blowing system according to claim 2, wherein: The carbon dioxide storage unit is a liquefied gas storage tank for storing liquid carbon dioxide, and a carbon dioxide gasification unit is provided on the inlet side of the carbon dioxide main pipe; alternatively, the carbon dioxide storage unit is a gas storage cabinet for storing gaseous carbon dioxide, and a carbon dioxide gasification unit is provided on the carbon dioxide delivery pipe of the liquefaction and purification device.

4. The converter blowing system according to claim 1, wherein: The fuel inlet of the hot blast stove is connected to a converter gas pipe and / or a blast furnace gas pipe.

5. The converter blowing system according to claim 1, wherein: A main pipe valve control unit is arranged on the carbon dioxide main pipe, and the main pipe valve control unit at least includes a pressure regulating valve and a stop valve.

6. The converter blowing system according to claim 5, wherein: The manifold valve control unit further includes a flow regulating valve and a flow meter interlocked with the flow regulating valve, wherein the flow regulating valve and the flow meter are arranged downstream of the pressure regulating valve.

7. The converter blowing system according to claim 1, wherein: There are two oxygen main pipes, and the outlet end of the carbon dioxide main pipe is connected to two carbon dioxide branch pipes. The two carbon dioxide branch pipes are respectively connected to the two oxygen main pipes, and the two carbon dioxide main pipes are respectively provided with branch pipe valve control units.

8. The converter blowing system according to claim 7, wherein: The branch pipe valve control unit comprises a stop valve, a quick-cut valve and a check valve which are sequentially arranged along the flow direction of carbon dioxide.

9. The converter blowing system according to claim 1, wherein: The oxygen main pipe is also connected to a nitrogen main pipe.

10. The converter blowing system according to claim 1, wherein: An oxygen lance valve chamber is also provided. The oxygen main pipe and the carbon dioxide main pipe are both arranged in the oxygen lance valve chamber, and the pipeline inlet and the pipeline outlet both extend out of the oxygen lance valve chamber.

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