Converter bottom blowing lime powder and oxygen feeding device and feeding method

Abstract

The invention discloses a feeding device and a feeding method for converter bottom blowing lime powder and oxygen. The feeding device comprises a combustion chamber, a combustor, a pressurizer and a mixer. The combustor is arranged in the combustion chamber, the pressurizer is provided with a pressurizing part for pressurizing gas, a pressurizing inlet and a pressurizing outlet, and the pressurizing inlet is communicated with a high-temperature gas outlet of the combustion chamber; the mixer is provided with a lime powder inlet, a pressurized gas inlet and a mixed outlet, the pressurized gas inlet is communicated with the pressurized outlet of the pressurizer, and the mixed outlet is used for being communicated with a bottom blowing gun of the converter. According to the feeding device, the problems that heat cannot be provided and the service life of a bottom blowing gun is short in a traditional converter bottom blowing oxygen lime powder process are solved, the steel scrap ratio of the converter is remarkably increased, the service life of the converter bottom is remarkably prolonged, meanwhile, the end point effect of the converter is improved, and the higher dephosphorization rate is achieved under the conditions that lime consumption is lower and slag T.Fe is lower.

Description

Technical Field

[0001] The invention belongs to the technical field of converter bottom blowing devices, and in particular relates to a feed device and a feed method for converter bottom blowing lime powder and oxygen. Background Art

[0002] Compared with the ordinary top-blown oxygen and bottom-blown inert gas converter process, the converter bottom-blown oxygen and lime powder steelmaking technology is a steelmaking method that uses O2 as a carrier gas to transport and spray lime powder into the molten pool at the bottom of the converter. The technology of spraying lime powder with oxygen as a carrier gas has the advantages of strong stirring, high iron recovery rate, significantly reduced lime consumption, reduced slag T.Fe, increased dephosphorization rate and increased metal recovery rate. However, compared with the ordinary converter process, the converter bottom-blown oxygen lime powder process has the characteristics of relatively lower slag T.Fe, lower secondary combustion of furnace gas, and larger bottom-blown gas flow, resulting in a relatively low scrap steel ratio of about 1%-2%, and bottom-blowing oxygen reduces the life of the furnace bottom.

[0003] Therefore, the process of blowing lime powder at the bottom of the converter has a significant advantage in improving the metallurgical effect of the converter, but it faces the problems of lower scrap steel ratio and short furnace bottom life. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a feeding device and feeding method for lime powder and oxygen for bottom blowing of a converter, which can effectively increase the scrap steel ratio of the converter, improve the dephosphorization effect, reduce the lime powder consumption, and increase the service life of the bottom blowing gun.

[0005] The technical solution of the present invention is:

[0006] In one aspect, the present invention provides a feeding device for bottom-blown lime powder and oxygen for a converter, which is used to feed the converter, and the feeding device comprises:

[0007] A combustion chamber having a fuel gas inlet, an oxygen inlet and a high-temperature gas outlet;

[0008] A burner, disposed in the fuel chamber;

[0009] A pressurizer, provided with a pressurizing portion for pressurizing the gas, a pressurizing inlet and a pressurizing outlet, wherein the pressurizing inlet is connected to the high-temperature gas outlet of the combustion chamber;

[0010] The mixer is provided with a lime powder inlet, a pressurized gas inlet and a mixing outlet, wherein the pressurized gas inlet is connected with the pressurized outlet of the pressurizer, and the mixing outlet is used to be connected with the bottom blowing gun of the converter.

[0011] Furthermore, the feeding device further comprises:

[0012] The buffer tank is provided with a buffer inlet and a buffer outlet, wherein the buffer inlet is communicated with the high-temperature gas outlet of the combustion chamber, and the buffer outlet is communicated with the pressurization inlet of the pressurizer.

[0013] Furthermore, a temperature sensor is provided at the high temperature gas outlet of the combustion chamber.

[0014] Furthermore, the feeding device further comprises:

[0015] Three regulating valves are respectively arranged at the fuel gas inlet, the oxygen inlet and the high-temperature gas outlet.

[0016] Furthermore, the feeding device further comprises:

[0017] An inert gas supply pipe has one end connected to an inert gas source and the other end connected to a mixing outlet of the mixer and a bottom blowing gun of the converter.

[0018] In a second aspect, the present invention further provides a feeding method, which is performed using the above-mentioned feeding device, and is characterized in that the feeding method comprises:

[0019] The fuel gas containing carbon and hydrogen elements enters into the chamber of the combustion chamber through the fuel gas inlet, and oxygen enters into the chamber of the combustion chamber through the oxygen inlet;

[0020] The fuel gas in the combustion chamber undergoes an exothermic reaction under the action of the burner in the combustion chamber and mixes with the oxygen for heat exchange to obtain high-temperature gas;

[0021] The high temperature gas is discharged from the high temperature gas outlet of the combustion chamber and is pressurized by the pressurizing part of the pressurizer to obtain pressurized gas;

[0022] The pressurized gas enters the mixing chamber of the mixer from the pressurized gas inlet, mixes with the lime powder entering the mixing chamber from the lime powder inlet, and is discharged from the mixing outlet through the bottom blowing gun of the converter into the converter molten pool to complete the gas supply.

[0023] Furthermore, the feeding method further comprises:

[0024] According to the high temperature gas temperature at the high temperature gas outlet of the combustion chamber, the opening of the regulating valve at the fuel gas inlet, the oxygen inlet and the high temperature gas outlet of the combustion chamber is determined, specifically:

[0025] When the high temperature gas temperature at the high temperature gas outlet is lower than 500° C., the opening of the regulating valve at the fuel gas inlet becomes larger, and the opening of the regulating valve at the high temperature gas outlet becomes smaller;

[0026] When the high-temperature gas temperature at the high-temperature gas outlet is 500-800° C., the opening of the regulating valve at the high-temperature gas outlet becomes larger;

[0027] When the high temperature gas temperature at the high temperature gas outlet is higher than 800°C, the opening of the regulating valve at the oxygen inlet becomes larger or the opening of the regulating valve at the fuel gas inlet becomes smaller, and at the same time, the opening of the regulating valve at the high temperature gas outlet becomes smaller;

[0028] Furthermore, the fuel gas includes combustible gas and combustion-supporting gas, and the combustible gas is methane or coal gas.

[0029] Furthermore, in the exothermic reaction, the combustible gas is completely burned.

[0030] Furthermore, the particle size of the lime powder is 20-200 mesh.

[0031] The beneficial effects of the present invention include at least:

[0032] The present invention provides a feed device for bottom-blowing lime powder and oxygen for a converter, which is used for feeding the converter, and the feed device comprises a combustion chamber, a burner, a pressurizer and a mixer. The combustion chamber is provided with a fuel gas inlet, an oxygen inlet and a high-temperature gas outlet; the burner is arranged in the combustion chamber, the pressurizer is provided with a pressurizing part for pressurizing the gas, a pressurizing inlet and a pressurizing outlet, and the pressurizing inlet is connected with the high-temperature gas outlet of the combustion chamber; the mixer is provided with a lime powder inlet, a pressurized gas inlet and a mixing outlet, the pressurized gas inlet is connected with the pressurized outlet of the pressurizer, and the mixing outlet is used to be connected with the bottom-blowing gun of the converter. Fuel and combustion-supporting gas containing carbon and hydrogen elements enter the chamber of the combustion chamber from the fuel gas inlet and burn, an exothermic reaction occurs and carbon dioxide gas and water vapor are generated. The oxygen entering from the oxygen inlet is heated by the heat generated by the combustion in the combustion chamber as a carrier to form high-temperature oxygen; the mixed gas formed by the high-temperature oxygen, high-temperature carbon dioxide and water vapor in the combustion chamber enters the pressurizer along the high-temperature gas outlet, and after being pressurized by the pressurizing part, enters the mixing chamber of the mixer from the pressurized gas inlet. Lime powder also enters the mixing chamber of the mixer from the lime powder inlet, and the lime powder is heated by the pressurized high-temperature gas. The high-temperature pressurized gas will be used as a carrier to carry the high-temperature lime powder and be discharged from the mixing outlet and blown into the converter molten pool through the converter bottom blowing gun; due to the pressurized gas Both the carbon dioxide and lime powder are heated before entering the converter, so the solution temperature in the converter will not be reduced, thereby not affecting the amount of scrap steel added and the scrap steel ratio; the carbon dioxide gas produced by the combustion reaction will also enter the molten pool along with the oxygen and lime powder, and the carbon dioxide will chemically react with the carbon in the molten pool to form twice the volume of carbon monoxide, thereby improving the kinetic conditions of molten pool stirring, further improving the dephosphorization effect of lime powder, reducing the consumption of lime powder, and promoting slag-steel reaction, significantly reducing the T.Fe content of the slag; at the same time, since the chemical reaction between carbon dioxide and carbon in the molten pool is an endothermic reaction, it has a cooling effect on the side of the bottom blowing gun close to the molten pool, which can slow down the erosion of the high-temperature molten pool on the bottom blowing gun and increase the service life of the bottom blowing gun. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic structural diagram of a feeding device of this embodiment.

[0034] Description of reference numerals:

[0035] 1-combustion chamber, 11-fuel gas inlet, 12-oxygen inlet, 13-high-temperature gas outlet; 2-buffer tank; 3-pressurizer; 4-mixer; 5-inert gas supply pipe; 6-converter; 7-regulating valve; 8-powder spray tank. DETAILED DESCRIPTION

[0036] In order to enable technicians in the technical field to which the present application belongs to understand the present application more clearly, the technical solution of the present application is described in detail below through specific embodiments in conjunction with the accompanying drawings.

[0037] In the related art, the top-blowing part oxygen and the bottom-blowing part oxygen converter smelting will result in less heat generation and reduce the scrap ratio. The embodiment of the present application provides a feed device and a feed method for bottom-blowing lime powder and oxygen in a converter, which at least improves the scrap ratio to a certain extent.

[0038] In the first aspect, the embodiment of the present invention provides a feeding device for feeding the converter 6. Figure 1 The feeding device includes a combustion chamber 1, a burner, a pressurizer 3 and a mixer 4. The combustion chamber 1 is provided with a fuel gas inlet 11, an oxygen inlet 12 and a high-temperature gas outlet 13; the burner is arranged in the combustion chamber 1, the pressurizer 3 is provided with a pressurizing part for pressurizing the gas, a pressurizing inlet and a pressurizing outlet, and the pressurizing inlet is connected with the high-temperature gas outlet 13 of the combustion chamber 1; the mixer 4 is provided with a lime powder inlet, a pressurized gas inlet and a mixing outlet, the pressurized gas inlet is connected with the pressurized outlet of the pressurizer 3, and the mixing outlet is used to be connected with the bottom blowing gun of the converter 6.

[0039] Fuel and combustion-supporting gas containing carbon and hydrogen elements enter the chamber of the combustion chamber 1 from the fuel gas inlet 11 and burn, causing an exothermic reaction to generate carbon dioxide gas and water vapor. The oxygen entering from the oxygen inlet 12 is heated by the heat generated by the combustion in the combustion chamber 1 as a carrier to form high-temperature oxygen; the mixed gas formed by the high-temperature oxygen, high-temperature carbon dioxide and water vapor in the combustion chamber 1 enters the pressurizer 3 along the high-temperature gas outlet 13, and after being pressurized by the pressurized part, enters the mixing chamber of the mixer 4 from the pressurized gas inlet. Lime powder also enters the mixing chamber of the mixer 4 from the lime powder inlet. The lime powder will be heated by the pressurized high-temperature gas, and the high-temperature pressurized gas will be used as a carrier to carry the high-temperature lime powder and be discharged from the mixing outlet and pass through the bottom of the converter 6. The blow gun blows into the molten pool of the converter 6; since the pressurized gas and the lime powder are heated before entering the converter 6, the solution temperature in the converter 6 will not be reduced, thereby not affecting the amount of scrap steel added and the scrap steel ratio; the carbon dioxide gas produced by the combustion reaction will also enter the molten pool along with the oxygen and the lime powder, and the carbon dioxide will chemically react with the carbon in the molten pool to form twice the volume of carbon monoxide, thereby improving the kinetic conditions for stirring the molten pool, further improving the dephosphorization effect of the lime powder, and reducing the consumption of lime powder; at the same time, since the chemical reaction between carbon dioxide and the carbon in the molten pool is an endothermic reaction, it has a cooling effect on the side of the bottom blowing gun close to the molten pool, which can slow down the erosion of the high-temperature molten pool on the bottom blowing gun and increase the service life of the bottom blowing gun.

[0040] The burner may be a burner, and the burner may be arranged at the inlet of the fuel gas. The combustion chamber 1 may also be provided with a pressure relief valve for relieving the pressure in the combustion chamber 1. The feeding device may also include a powder spraying tank 8, and the ash spraying port of the powder spraying tank 8 is connected to the lime powder inlet of the mixer 4.

[0041] Furthermore, in this embodiment, combined with Figure 1 The feeding device may further include a buffer tank 2, wherein the buffer tank 2 is provided with a buffer inlet and a buffer outlet, wherein the buffer inlet is connected to the high-temperature gas outlet 13 of the combustion chamber 1, and the buffer outlet is connected to the pressurized inlet of the pressurizer 3. The high-temperature gas in the combustion chamber 1 may be temporarily stored in the buffer tank 2 to ensure the stability of the lime powder carrier. The inner cavity volume of the buffer tank 2 may be designed according to requirements. In other embodiments, the outer shell of the buffer tank 2 may be wrapped with a layer of heat-insulating material to insulate the high-temperature gas in the buffer tank 2 and prevent heat loss.

[0042] In order to detect the temperature of the high temperature gas discharged from the combustion chamber 1, in this embodiment, a temperature sensor may be provided at the high temperature gas outlet 13 of the combustion chamber 1. The temperature sensor may be selected from the prior art and is not limited here.

[0043] Furthermore, in this embodiment, in order to adjust the flow rate of the gas path, the feeding device may also include three regulating valves 7, which are respectively arranged at the fuel gas inlet 11, the oxygen inlet 12 and the high-temperature gas outlet 13 to adjust the amount of fuel gas entering the combustion chamber 1, the amount of oxygen entering and the amount of high-temperature gas discharged. The regulating valve 7 handles flow regulation and may also have an opening and closing function; of course, in other embodiments, a regulating valve 7 with only a flow regulation function may be selected, and then three opening and closing valves may be added accordingly to realize the on-off of the fuel gas inlet 11, the oxygen inlet 12 and the high-temperature gas outlet 13. The specific method of selection is not limited here.

[0044] Furthermore, in this embodiment, the feeding device may also include an inert gas supply pipe 5, one end of which is used to communicate with the inert gas source, and the other end of which is connected to the mixing outlet of the mixer 4 and the bottom blowing gun of the converter 6. The inert gas supply pipe 5 can provide an inert gas source for the converter 6 molten pool, such as any one of N2, Ar and a mixed gas thereof. According to production needs, high-temperature oxygen can be blown into the bottom of the converter 6 as lime powder with a carrier, or inert gas can be blown into the bottom of the converter 6 for stirring.

[0045] Based on the same inventive concept, in a second aspect, an embodiment of the present invention further provides a feeding method, which is performed using the above-mentioned converter bottom blowing lime powder and oxygen feeding device, and the feeding method comprises:

[0046] S1, the fuel gas containing carbon and hydrogen elements enters into the chamber of the combustion chamber 1 through the fuel gas inlet 11, and oxygen enters into the chamber of the combustion chamber 1 through the oxygen inlet 12;

[0047] Furthermore, in this embodiment, the fuel gas includes a combustible gas and a combustion-supporting gas, and the combustible gas is methane or coal gas.

[0048] S2, the fuel gas in the combustion chamber undergoes an exothermic reaction under the action of the burner in the combustion chamber 1, and mixes with oxygen for heat exchange to obtain high-temperature gas;

[0049] Furthermore, in this embodiment, the combustible gas is completely burned in the exothermic reaction. Specifically, if the combustible gas is methane and the combustion-supporting gas is oxygen, the volume ratio of the combustible gas to the combustion-supporting gas is 1:2-8, that is, the combustion-supporting gas is excessive to avoid incomplete combustion of the combustible gas.

[0050] S3, the high temperature gas is discharged from the high temperature gas outlet 13 of the combustion chamber 1 and is pressurized by the pressurizing part of the pressurizer 3 to obtain pressurized gas;

[0051] S4, the pressurized gas enters the mixing chamber of the mixer 4 from the pressurized gas inlet, and is mixed with the lime powder entering the mixing chamber from the lime powder inlet, and is discharged from the mixing outlet through the bottom blowing gun of the converter 6 into the molten pool of the converter 6 to complete the gas supply.

[0052] Furthermore, in this embodiment, the particle size of the lime powder may be 20-200 mesh.

[0053] The pressurized gas in the mixing chamber includes oxygen entering from the oxygen inlet 12 of the combustion chamber 1, and also includes carbon dioxide and water vapor produced by the exothermic reaction. The high-pressure gas formed by the three is used as a carrier of lime powder. The bottom blowing intensity of the bottom blowing gun of the high-pressure gas entering the converter 6 can be 0.3-0.6Nm 3 / t / min, the mass volume ratio of lime powder to high pressure gas can be 4.0~8.0kg / Nm 3 .

[0054] Since the water vapor in the mixing chamber exists in the form of high-speed gas, after the water vapor is mixed with the lime powder, not only will the lime powder not absorb water and agglomerate, but the high-speed and high-pressure gas can also further crush the lime powder.

[0055] Furthermore, in this embodiment, the feeding method further comprises:

[0056] According to the high temperature gas temperature at the high temperature gas outlet 13 of the combustion chamber 1, the opening of the regulating valve 7 at the fuel gas inlet 11, the oxygen inlet 12 and the high temperature gas outlet 13 of the combustion chamber 1 is determined, specifically:

[0057] When the high-temperature gas temperature at the high-temperature gas outlet 13 is lower than 500°C, the opening of the regulating valve 7 at the fuel gas inlet 11 becomes larger, and the opening of the regulating valve 7 at the high-temperature gas outlet 13 becomes smaller, the fuel gas flow rate is controlled at 0.2-0.5Nm3 / t / min, such as 0.3Nm3 / t / min, 0.35Nm3 / t / min, 0.4Nm3 / t / min or 0.45Nm3 / t / min, and the oxygen flow rate is controlled at 0.4-1.0Nm3 / t / min, such as 0.45Nm3 / t / min, 0.5Nm3 / t / min, 0.6Nm3 / t / min, 0.65Nm3 / t / min, 0.7Nm3 / t / min, 0.75Nm3 / t / min, 0.8Nm3 / t / min, 0.85Nm3 / t / min or 0.9Nm3 / t / min, etc.;

[0058] When the high-temperature gas temperature at the high-temperature gas outlet 13 is 500-1000°C, the opening of the regulating valve 7 at the high-temperature gas outlet 13 becomes larger, and the gas flow rate is controlled at 0.1-0.3Nm3 / t / min, such as 0.15Nm3 / t / min, 0.2Nm3 / t / min, 0.25Nm3 / t / min or 0.28Nm3 / t / min, and the oxygen flow rate is controlled at 0.4-1.0Nm3 / t / min, such as 0.45Nm3 / t / min, 0.5Nm3 / t / min, 0.6Nm3 / t / min, 0.7Nm3 / t / min, 0.8Nm3 / t / min or 0.9Nm3 / t / min;

[0059] When the high temperature gas temperature at the high temperature gas outlet 13 is higher than 1000°C, the opening of the regulating valve 7 at the oxygen inlet 12 becomes larger or the opening of the regulating valve 7 at the fuel gas inlet 11 becomes smaller, and the opening of the regulating valve 7 at the high temperature gas outlet 13 becomes smaller, and the gas flow rate is controlled at 0.05-0.1Nm3 / t / min, for example, 0.06Nm3 / t / min, 0.08Nm3 / t / min, 0.09Nm3 / t / min or 0.95Nm3 / t / min. m3 / t / min, etc., the oxygen flow rate is controlled at 0.4-1.0Nm3 / t / min, such as 0.45Nm3 / t / min, 0.5Nm3 / t / min, 0.6Nm3 / t / min, 0.65Nm3 / t / min, 0.7Nm3 / t / min, 0.75Nm3 / t / min, 0.8Nm3 / t / min, 0.85Nm3 / t / min or 0.9Nm3 / t / min, etc.;

[0060] That is, when the amount of high temperature gas in the combustion chamber 1 is insufficient, the reaction amount of the fuel gas is increased and the amount of high temperature gas discharged from the combustion chamber is reduced.

[0061] Calculation basis: gas flow rate is 3Nm3 / t, gas calorific value is 36000kJ / Nm3, heat brought is 108000kJ / t steel. The heat required for 1t molten steel and corresponding slag and furnace gas to rise by 1℃ is 1073.3kJ / mol. The thermal efficiency is estimated to be 70%, and the temperature of molten steel is relatively increased by 70.4℃ / t steel.

[0062] Example 1 to Example 5

[0063] Embodiments 1 to 5 all provide a feeding method, which is carried out using the aforementioned feeding device, and is specifically as follows:

[0064] (1) Before the combustion chamber 1 is ignited, when the converter 6 is being charged with scrap steel or iron, N2 is blown toward the bottom of the converter 6 through the inert gas supply pipe 5.

[0065] (2) After the start of smelting, CH4 as fuel and O2 as combustion support are respectively connected to the water-cooled burner buried in the refractory material of combustion chamber 1. CH4 is ignited by an igniter at the burner outlet to generate a high-temperature flame. The ratio of CH4 flow rate to combustion support O2 is maintained at 1:6 to ensure that there is no residual CH4 in combustion chamber 1; and the gas pressure in combustion chamber 1 is controlled not to exceed the set value of the bottom blowing O2 pressure of converter 6.

[0066] (3) When the combustion is stable, oxygen at room temperature is introduced into the combustion chamber 1 through the oxygen inlet 12. The gas from the combustion chamber 1 reaches 500-800°C and enters the buffer tank 2, and then replaces N2 to enter the molten pool from the bottom of the converter 6. At the same time, the valve of the powder spraying tank 8 is opened for powder spraying.

[0067] (4) The temperature of the hot carrier gas is adjusted by changing the flow rate of CH4. When the temperature is lower than the set temperature, the gas supply in the burner is increased; when the temperature is higher than the set temperature, the gas supply in the burner is reduced.

[0068] (5) After the bottom blowing of O2 and lime powder is completed, the valves of the bottom blowing O2 and lime powder pipelines are closed, the bottom blowing gas is switched to N2, and then converter 6 performs operations such as steel tapping and slag splashing to protect the furnace.

[0069] (6) After the bottom blowing of N2 begins, stop introducing room temperature O2 as a carrier gas into the combustion chamber 1 and keep the burner in a combustion state with a minimum gas supply to prevent residual CH4 from being contained in the combustion chamber 1.

[0070] (7) After adding scrap steel and iron to the next furnace, switch the bottom blowing gas to O2, increase the burner gas supply and proceed according to step (3).

[0071] Comparative Example 1

[0072] Comparative Example 1 provides a traditional feeding method, which is as follows:

[0073] The lime powder is sprayed into the molten pool of the converter 6 through the bottom blowing gun of the converter 6 using oxygen at room temperature as a carrier.

[0074] Comparative Example 2

[0075] Comparative Example 2 provides a traditional converter smelting method, which adopts the process of blowing oxygen from the top and blowing N2 and Ar gas from the bottom for smelting.

[0076] Table 1

[0077]

[0078] Table 2

[0079]

[0080] It can be seen from the data in Table 2 that when the device provided by Examples 1 to 5 of the present invention is used for smelting, the scrap steel ratio is 20.1-21.3%, the scrap steel ratio is high, the dephosphorization rate is 95.3-96.2%, the dephosphorization effect is good, the amount of lime powder is 19-23 kg / t, the amount of lime powder is low, the slag T.Fe is reduced to below 10%, and the furnace bottom life is increased to about 2500-3000 furnaces.

[0081] The feeding device provided by the present invention has at least the following advantages for converter feeding and smelting:

[0082] 1) Lime powder and oxygen are heated by fuel combustion, which significantly increases the heat and the scrap steel ratio.

[0083] 2) The carbon dioxide gas formed by the combustion reaction enters the converter together to play a stirring role, thereby improving the dephosphorization effect of the lime powder and reducing the consumption of lime powder.

[0084] 3) The chemical reaction between the carbon dioxide gas formed by the combustion reaction and the carbon in the molten pool is an endothermic reaction, which has a cooling effect on the bottom blowing gun, thereby extending the service life of the bottom blowing gun.

[0085] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present application.

[0086] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A feeding device for bottom blowing lime powder and oxygen for a converter, used for feeding the converter, characterized in that: The feeding device comprises: A combustion chamber having a fuel gas inlet, an oxygen inlet and a high-temperature gas outlet; A burner, disposed at the fuel gas inlet; A pressurizer, provided with a pressurizing portion for pressurizing the gas, a pressurizing inlet and a pressurizing outlet, wherein the pressurizing inlet is connected to the high-temperature gas outlet of the combustion chamber; The mixer is provided with a lime powder inlet, a pressurized gas inlet and a mixing outlet, wherein the pressurized gas inlet is connected with the pressurized outlet of the pressurizer, and the mixing outlet is used to be connected with the bottom blowing gun of the converter.

2. The feed device for bottom-blown lime powder and oxygen according to claim 1, characterized in that: Also includes: The buffer tank is provided with a buffer inlet and a buffer outlet, wherein the buffer inlet is communicated with the high-temperature gas outlet of the combustion chamber, and the buffer outlet is communicated with the pressurization inlet of the pressurizer.

3. The feed device for bottom-blown lime powder and oxygen according to claim 1, characterized in that: A temperature sensor is provided at the high temperature gas outlet of the combustion chamber.

4. The feed device for bottom-blown lime powder and oxygen according to claim 1, characterized in that: Also includes: Three regulating valves are respectively arranged at the fuel gas inlet, the oxygen inlet and the high-temperature gas outlet.

5. The feed device for lime powder and oxygen for bottom blowing of a converter according to any one of claims 1 to 4, characterized in that: Also includes: An inert gas supply pipe has one end connected to an inert gas source and the other end connected to a mixing outlet of the mixer and a bottom blowing gun of the converter.

6. A feeding method, using the feeding device for bottom blowing lime powder and oxygen of a converter according to any one of claims 1 to 5, characterized in that: The feeding method comprises: The fuel gas containing carbon and hydrogen elements enters into the chamber of the combustion chamber through the fuel gas inlet, and oxygen enters into the chamber of the combustion chamber through the oxygen inlet; The fuel gas in the chamber of the combustion chamber reacts with oxygen under the action of the burner in the combustion chamber to produce high-temperature gas; The high temperature gas is discharged from the high temperature gas outlet of the combustion chamber and is pressurized by the pressurizing part of the pressurizer to obtain pressurized gas; The pressurized gas enters the mixing chamber of the mixer from the pressurized gas inlet, mixes with the lime powder entering the mixing chamber from the lime powder inlet, and is discharged from the mixing outlet, and enters the converter molten pool from the bottom blowing gun of the converter to complete the feeding.

7. The feeding method according to claim 6, characterized in that: Also includes: According to the high temperature gas temperature at the high temperature gas outlet of the combustion chamber, the opening of the regulating valve at the fuel gas inlet is adjusted, specifically: When the high temperature gas temperature at the high temperature gas outlet is 500-1000°C, the flow rate of the fuel gas is 0.1-0.3Nm3 / t / min; When the high temperature gas temperature at the high temperature gas outlet is lower than 500°C, the fuel gas flow rate is 0.2-0.5Nm3 / t / min; When the high-temperature gas temperature at the high-temperature gas outlet is higher than 1000° C., the fuel gas flow rate is 0.05-0.1 Nm 3 / t / min.

8. The feeding method according to claim 6, characterized in that: The fuel gas includes combustible gas and combustion-supporting gas, and the combustible gas is at least one of natural gas, AC gas, blast furnace gas and converter gas.

9. The feeding method according to claim 6, characterized in that: In the exothermic reaction, the combustible gas is completely burned.

10. The feeding method according to claim 6, characterized in that: The particle size of the lime powder is 20-200 meshes.

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