Blast furnace hydrogen-rich gas injection hearth heat control method

Abstract

The invention relates to a blast furnace hydrogen-rich gas injection hearth heat control method, the blast furnace comprises a furnace shell, the furnace shell is provided with at least four tap holes and at least four tuyeres, and the at least four tap holes and the at least four tuyeres are uniformly arranged along the circumferential direction of the furnace shell at intervals. If yes, four tuyeres evenly distributed in the circumferential direction of the furnace shell are synchronously opened to conduct injection of hydrogen-rich gas; if the blowing amount per ton of iron is larger than or equal to the first preset value and smaller than or equal to the second preset value, a plurality of tuyeres spaced in the circumferential direction of the furnace shell are synchronously opened to conduct hydrogen-rich gas blowing, and the number of the synchronously-opened tuyeres is larger than four; and if the blowing amount per ton of iron is larger than the second preset value, all tuyeres in the circumferential direction of the furnace shell are synchronously opened to conduct hydrogen-rich gas blowing, and the number of the synchronously-opened tuyeres is larger than four. The technical problems that the activity of the blast furnace hearth becomes poor and the yield of the blast furnace is reduced due to non-uniform injection of the hydrogen-rich gas in the circumferential direction of the blast furnace are solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of steel smelting, further relates to a blast furnace hydrogen-rich gas injection furnace hearth heat control method, in particular to a control method which can make the blast furnace hydrogen-rich gas injection furnace hearth heat uniform. BACKGROUND

[0002] The steel industry is an energy resource consumption intensive industry, and the global ton steel carbon emission intensity in 2020 is about 1.89t, and the carbon emission accounts for about 7% of the global energy system emission. And the long process of blast furnace-converter (of which the CO2 emission intensity of blast furnace-converter long process per ton of steel is about 2.0t) accounts for a large proportion, and the application of hydrogen instead of carbon technology in the long process of steel will be the main way of future carbon reduction. Many steel enterprises are actively conducting blast furnace hydrogen-rich gas injection industrial tests, but all of them have the phenomenon of poor blast furnace operation effect caused by the increase of injection amount, and the blast furnace has the phenomena of yield reduction and cost increase, etc. The reason is that the use of hydrogen-rich gas, whether H2 decomposed from natural gas or H2 directly contained in coke oven gas and pure hydrogen gas, will absorb heat when entering the tuyere swirling area of the furnace hearth (i.e. the area range close to the tuyere in the furnace hearth), which will cause the combustion temperature to decrease, especially for the environment of non-uniform hydrogen-rich gas injection, which will further lead to the decrease of furnace hearth activity, the poor uniformity of furnace hearth circumferential temperature and the non-uniformity of furnace hearth circumferential heat, thereby affecting the smooth operation of the blast furnace and hindering the improvement of the blast furnace yield.

[0003] Chinese invention patent CN117165729A discloses a method for smelting vanadium-titanium magnetite with hydrogen-rich blast furnace and active furnace hearth, the number of tuyeres is 18, the number of tuyeres closest to the projection position of the tapping hole on the tuyere plane is two, and the length of the two tuyeres closest to the tapping hole is 450mm; the number of tuyeres farthest from the projection position of the tapping hole on the tuyere plane is four, and the length of the four farthest tuyeres is 420mm. It only adjusts the length of the tuyeres in different directions to change the blast kinetic energy, and cannot solve the problem of non-uniformity of the furnace hearth circumferential caused by the different circumferential theoretical combustion temperatures of the hydrogen-rich blast furnace from the heat angle.

[0004] For the problem of non-uniform hydrogen-rich gas injection in the circumferential direction of the blast furnace in the related art, which leads to the poor activity of the blast furnace hearth and the reduction of the blast furnace yield, there is no effective solution at present.

[0005] Therefore, the present application is proposed by the present inventor with years of experience and practice in the relevant industry to overcome the defects of the prior art. SUMMARY

[0006] The present application aims to provide a blast furnace hydrogen-rich gas injection hearth heat control method, which can ensure uniform injection of hydrogen-rich gas in the circumferential direction of the blast furnace, and can adjust other injection equipment according to the change of injection amount at different positions and the change of local injection equipment stop injection state, so as to ensure that the hydrogen-rich gas process will not cause local heat unevenness of the hearth, ensure the uniformity of the temperature in the circumferential direction of the hearth, ensure the smooth operation of the hearth, and improve the yield of the blast furnace.

[0007] The purpose of the present application can be achieved by the following scheme:

[0008] The present application provides a blast furnace hydrogen-rich gas injection hearth heat control method, wherein the blast furnace comprises a furnace shell, and the furnace shell is provided with at least four tapping holes and at least four tuyeres, and the plurality of tapping holes are arranged uniformly and spaced apart in the circumferential direction of the furnace shell, and the plurality of tuyeres are arranged uniformly and spaced apart in the circumferential direction of the furnace shell.

[0009] The blast furnace hydrogen-rich gas injection hearth heat control method comprises the following steps:

[0010] If the ton iron injection amount is less than a first preset value, the four tuyeres uniformly distributed in the circumferential direction of the furnace shell are synchronously opened to inject hydrogen-rich gas.

[0011] If the ton iron injection amount is greater than or equal to the first preset value and less than or equal to a second preset value, the plurality of tuyeres spaced apart in the circumferential direction of the furnace shell are synchronously opened to inject hydrogen-rich gas, and the number of synchronously opened tuyeres is more than four.

[0012] If the ton iron injection amount is greater than the second preset value, all the tuyeres in the circumferential direction of the furnace shell are synchronously opened to inject hydrogen-rich gas, and the number of synchronously opened tuyeres is more than four.

[0013] In a preferred embodiment of the present application, the furnace shell is in a cylindrical structure, the furnace shell is annularly arranged in the circumferential direction to form a hearth, and the tapping holes are staggered with the tuyeres.

[0014] In a preferred embodiment of the present application, the plurality of tapping holes are located on a first plane, and the plurality of tuyeres are located on a second plane, and the second plane is located above the first plane.

[0015] In a preferred embodiment of the present application, when the four tuyeres uniformly distributed in the circumferential direction of the furnace shell are synchronously opened to inject hydrogen-rich gas, or when the plurality of tuyeres spaced apart in the circumferential direction of the furnace shell are synchronously opened to inject hydrogen-rich gas, the tuyere located directly above the tapping hole or the tuyere vertically adjacent to the tapping hole is in a stop injection state.

[0016] In a preferred embodiment of the present application, the first preset value is 10 kg / ton of iron; and / or, the second preset value is 20 kg / ton of iron.

[0017] In a preferred embodiment of the present application, the blast furnace hydrogen-rich gas injection hearth heat control method further comprises:

[0018] If the opened multiple tuyeres turn to the stop-injection state, another tuyere opposite to the stop-injection tuyere in the circumferential direction of the furnace shell turns from the opened state to the stop-injection state.

[0019] In a preferred embodiment of the present application, the blast furnace hydrogen-rich gas injection hearth heat control method is provided with an interlock program for associating any two tuyeres opposite to each other in the circumferential direction of the furnace shell, so that the two tuyeres have the same working state.

[0020] In a preferred embodiment of the present application, when the taphole continuously taps iron for a second preset time, the taphole in the tapping state is controlled to turn to the stop-tapping state, and the taphole in the stop-tapping state is controlled to turn to the tapping state.

[0021] In a preferred embodiment of the present application, when the tuyere reduces the injection amount of hydrogen-rich gas into the hearth or stops injection, the injection amount of hydrogen-rich gas of all the tuyeres in the opened state changes in the same way.

[0022] In a preferred embodiment of the present application, if the tuyere injects a mixture of hydrogen-rich gas and pulverized coal into the hearth, when the injection amount of hydrogen-rich gas is reduced or stopped, the injection amount of pulverized coal is correspondingly increased, and the injection amount of hydrogen-rich gas of all the tuyeres in the opened state changes in the same way.

[0023] From the above, the blast furnace hydrogen-rich gas injection hearth heat control method of the present application has the following characteristics and advantages:

[0024] At least four tapholes and at least four tuyeres are arranged on the furnace shell of the blast furnace, and the plurality of tapholes and the plurality of tuyeres are respectively spaced and uniformly distributed along the circumference of the furnace shell; in the process of controlling the hydrogen-rich gas injection heat of the blast furnace hearth, the number of tuyeres opened and the position of the tuyeres are adjusted according to the ton iron injection amount, if the ton iron injection amount is less than a first preset value, four tuyeres uniformly distributed along the circumference of the furnace shell are synchronously opened for hydrogen-rich gas injection; if the ton iron injection amount is greater than or equal to the first preset value and less than or equal to a second preset value, a plurality of tuyeres spaced along the circumference of the furnace shell are synchronously opened for hydrogen-rich gas injection; if the ton iron injection amount is greater than the second preset value, all tuyeres along the circumference of the furnace shell are synchronously opened for hydrogen-rich gas injection, so that the other injection equipment is adaptively adjusted according to the change of the injection amount at different circumferential positions of the furnace shell and the change of the local injection equipment stop injection state, to ensure that the hydrogen-rich gas process will not cause local heat unevenness of the hearth, thereby ensuring uniform hydrogen-rich gas injection and heat along the circumference of the blast furnace, ensuring the smooth running of the hearth, and achieving the purpose of improving the output of the blast furnace. BRIEF DESCRIPTION OF DRAWINGS

[0025] The following drawings are only intended to illustrate and explain the present application, and do not limit the scope of the present application.

[0026] Among them:

[0027] Figure 1 : is a sectional view of the plane where the tuyere of the blast furnace in the hydrogen-rich gas injection hearth heat control method of the present application is located.

[0028] Figure 2 : is one of the working state schematic diagrams of the blast furnace in the hydrogen-rich gas injection hearth heat control method of the present application.

[0029] Figure 3 : is the second working state schematic diagram of the blast furnace in the hydrogen-rich gas injection hearth heat control method of the present application.

[0030] The reference numerals in the present application are:

[0031] 1, furnace shell; 101, taphole;

[0032] 102, tuyere. DETAILED DESCRIPTION

[0033] In order to have a clearer understanding of the technical features, purposes and effects of the present application, the specific embodiments of the present application will be described with reference to the drawings.

[0034] As Figure 1As shown, the present application provides a blast furnace hydrogen-rich gas injection hearth heat control method, the blast furnace comprises a furnace shell 1, the furnace shell 1 is cylindrical structure, the furnace shell 1 is circumferentially annularly formed into a hearth, the furnace shell 1 has at least four tapping holes 101 and at least four tuyeres 102, a plurality of tapping holes 101 are spaced and uniformly arranged along the circumference of the furnace shell 1, and a plurality of tuyeres 102 are spaced and uniformly arranged along the circumference of the furnace shell 1.

[0035] The blast furnace hydrogen-rich gas injection hearth heat control method comprises:

[0036] If the ton iron injection amount is less than the first preset value, then the four tuyeres 102 evenly distributed circumferentially on the furnace shell 1 are synchronously opened for hydrogen-rich gas injection;

[0037] If the ton iron injection amount is greater than or equal to the first preset value and less than or equal to the second preset value, then a plurality of tuyeres 102 spaced circumferentially on the furnace shell 1 are synchronously opened for hydrogen-rich gas injection, and the number of tuyeres 102 synchronously opened is more than four;

[0038] If the ton iron injection amount is greater than the second preset value, then all tuyeres 102 circumferentially on the furnace shell 1 are synchronously opened for hydrogen-rich gas injection, and the number of tuyeres 102 synchronously opened is more than four.

[0039] In the present application, at least four tapping holes 101 and at least four tuyeres 102 are arranged on the furnace shell 1 of the blast furnace, and the plurality of tapping holes 101 and the plurality of tuyeres 102 are respectively spaced and uniformly distributed circumferentially on the furnace shell 1; in the process of controlling the hydrogen-rich gas injection hearth heat of the blast furnace, the number of tuyeres 102 opened and the position of the tuyeres 102 are adjusted according to the ton iron injection amount; if the ton iron injection amount is less than the first preset value, then the four tuyeres 102 evenly distributed circumferentially on the furnace shell 1 are synchronously opened for hydrogen-rich gas injection; if the ton iron injection amount is greater than or equal to the first preset value and less than or equal to the second preset value, then a plurality of tuyeres 102 spaced circumferentially on the furnace shell 1 are synchronously opened for hydrogen-rich gas injection; if the ton iron injection amount is greater than the second preset value, then all tuyeres 102 circumferentially on the furnace shell 1 are synchronously opened for hydrogen-rich gas injection, thereby according to the change of the injection amount at different circumferential positions of the furnace shell 1 and the change of the local injection equipment stop injection state, the other injection equipment is adaptively adjusted, it is ensured that the hydrogen-rich gas process will not cause the local heat of the hearth to be uneven, thereby ensuring the uniform injection of the hydrogen-rich gas and the uniform heat of the blast furnace circumferentially, ensuring the smooth running of the hearth, and achieving the purpose of improving the yield of the blast furnace.

[0040] The hydrogen-rich gas or natural gas entering the furnace hearth from tuyere 102 on furnace shell 1 and near the area close to tuyere 102 will absorb heat due to decomposition, thereby reducing the theoretical combustion temperature (the theoretical combustion temperature of a single tuyere 102 can be reduced by 10-80°C), in order to ensure uniform circumferential heat distribution in the furnace hearth, therefore, the opening number and position of tuyere 102 can be adjusted according to the above control method to ensure uniform hydrogen-rich gas injection and uniform heat distribution in the circumferential direction of the blast furnace.

[0041] In an optional embodiment of the present application, the first preset value is 10 kg / ton of iron; and / or, the second preset value is 20 kg / ton of iron.

[0042] When the ton of iron injection amount is less than 10 kg / ton of iron (i.e. 10 kg of hydrogen-rich gas is needed for injecting 1 ton of iron), then four tuyeres 102 evenly distributed in the circumferential direction of furnace shell 1 are simultaneously opened for hydrogen-rich gas injection, the two tuyeres 102 opposite to each other form a "cross" diagonal line, since the ton of iron injection amount is less than 10 kg / ton of iron, the injection amount is small, only the four tuyeres 102 evenly distributed in the circumferential direction of furnace shell 1 need to be opened to meet the injection requirement and ensure uniform circumferential heat distribution in the furnace hearth, but it is necessary to ensure that the taphole 101 is staggered with the tuyere 102 to avoid affecting normal tapping. Specifically, as shown in FIG. 1, 1# tuyere, 8# tuyere, 15# tuyere and 22# tuyere can be opened, and each taphole 101 is located at the middle position in the circumferential direction between the two adjacent tuyeres 102 (i.e. the distance between the taphole 101 and its adjacent two tuyeres 102 is the same), 1# taphole is located at the middle position in the circumferential direction between 1# tuyere and 22# tuyere, 2# taphole is located at the middle position in the circumferential direction between 15# tuyere and 22# tuyere, 3# taphole is located at the middle position in the circumferential direction between 8# tuyere and 15# tuyere, and 4# taphole is located at the middle position in the circumferential direction between 1# tuyere and 8# tuyere. Figure 2 When the ton of iron injection amount is greater than or equal to 10 kg / ton of iron and less than or equal to 20 kg / ton of iron, then multiple tuyeres 102 spaced apart in the circumferential direction of furnace shell 1 are simultaneously opened for hydrogen-rich gas injection, the number of tuyeres 102 simultaneously opened is more than four, and the multiple tuyeres 102 opened still maintain that two tuyeres 102 opposite to each other in the circumferential direction of furnace shell 1, by adjusting the number and position of the tuyeres 102 opened, the injection requirement is met while ensuring uniform circumferential heat distribution in the furnace hearth, but it is necessary to ensure that the taphole 101 is staggered with the tuyere 102 to avoid affecting normal tapping. Specifically, as shown in FIG. 2, 1# tuyere, 8# tuyere, 15# tuyere, 22# tuyere, 29# tuyere, 36# tuyere, 43# tuyere and 50# tuyere can be opened, and each taphole 101 is located at the middle position in the circumferential direction between the two adjacent tuyeres 102 (i.e. the distance between the taphole 101 and its adjacent two tuyeres 102 is the same), 1# taphole is located at the middle position in the circumferential direction between 1# tuyere and 22# tuyere, 2# taphole is located at the middle position in the circumferential direction between 15# tuyere and 22# tuyere, 3# taphole is located at the middle position in the circumferential direction between 8# tuyere and 15# tuyere, 4# taphole is located at the middle position in the circumferential direction between 1# tuyere and 8# tuyere, 5# taphole is located at the middle position in the circumferential direction between 22# tuyere and 29# tuyere, 6# taphole is located at the middle position in the circumferential direction between 36# tuyere and 43# tuyere, 7# taphole is located at the middle position in the circumferential direction between 43# tuyere and 50# tuyere, and 8# taphole is located at the middle position in the circumferential direction between 1# tuyere and 36# tuyere.

[0043] Figure 3 ​As shown, the 1# tuyere, the 3# tuyere, the 6# tuyere, the 8# tuyere, the 10# tuyere, the 13# tuyere, the 15# tuyere, the 17# tuyere, the 20# tuyere, the 22# tuyere, the 24# tuyere and the 27# tuyere can be opened, and at least one tuyere 102 in a stop-blowing state exists between two adjacent tuyeres 102 in an open state, for example, the 2# tuyere between the 1# tuyere and the 3# tuyere is in a stop-blowing state, the 4# tuyere and the 5# tuyere between the 3# tuyere and the 6# tuyere are in a stop-blowing state, the 7# tuyere between the 6# tuyere and the 8# tuyere is in a stop-blowing state, the 9# tuyere between the 8# tuyere and the 10# tuyere is in a stop-blowing state, the 11# tuyere and the 12# tuyere between the 10# tuyere and the 13# tuyere are in a stop-blowing state, the 14# tuyere between the 13# tuyere and the 15# tuyere is in a stop-blowing state, the 16# tuyere between the 15# tuyere and the 17# tuyere is in a stop-blowing state, the 18# tuyere and the 19# tuyere between the 17# tuyere and the 20# tuyere are in a stop-blowing state, the 21# tuyere between the 20# tuyere and the 22# tuyere is in a stop-blowing state, the 23# tuyere between the 22# tuyere and the 24# tuyere is in a stop-blowing state, and the 25# tuyere and the 26# tuyere between the 24# tuyere and the 27# tuyere are in a stop-blowing state. Since the 4# tuyere between the 3# tuyere and the 6# tuyere, the 3# tuyere between the 10# tuyere and the 13# tuyere, the 2# tuyere between the 7# tuyere and the 20# tuyere and the 1# tuyere between the 24# tuyere and the 27# tuyere have the taphole 101, two tuyeres 102 in a stop-blowing state exist between two adjacent tuyeres 102 in an open state.

[0044] In an optional embodiment of the present application, the plurality of tapholes 101 are located on a first plane, and the plurality of tuyeres 102 are located on a second plane, and the second plane is located above the second plane, so that the tuyeres 102 are staggered with the tapholes 101. Preferably, the tapholes 101 and the tuyeres 102 are not in the same vertical line, so that a better avoiding effect is achieved, and the normal tapping is not affected.

[0045] Further, when the four tuyeres 102 uniformly distributed in the circumferential direction of the furnace shell 1 are simultaneously opened to spray the hydrogen-rich gas, or when the plurality of tuyeres 102 spaced apart in the circumferential direction of the furnace shell 1 are simultaneously opened to spray the hydrogen-rich gas, the tuyere 102 located directly above the taphole 101 or the tuyere 102 vertically adjacent to the taphole 101 is in a stop-blowing state. Figure 2As shown, when the 1# tuyere, the 8# tuyere, the 15# tuyere and the 22# tuyere are opened for blowing, the 26# tuyere and the 25# tuyere close to the 1# taphole are in the state of stopping blowing, the 18# tuyere and the 19# tuyere close to the 2# taphole are in the state of stopping blowing, the 11# tuyere and the 12# tuyere close to the 3# taphole are in the state of stopping blowing, and the 4# tuyere and the 5# tuyere close to the 4# taphole are in the state of stopping blowing. Figure 3 As shown, when the 1# tuyere, the 3# tuyere, the 4# tuyere, the 6# tuyere, the 8# tuyere, the 10# tuyere, the 13# tuyere, the 15# tuyere, the 17# tuyere, the 20# tuyere, the 22# tuyere, the 24# tuyere and the 27# tuyere are opened for blowing, the 26# tuyere and the 25# tuyere close to the 1# taphole are in the state of stopping blowing, the 18# tuyere and the 19# tuyere close to the 2# taphole are in the state of stopping blowing, the 11# tuyere and the 12# tuyere close to the 3# taphole are in the state of stopping blowing, and the 4# tuyere and the 5# tuyere close to the 4# taphole are in the state of stopping blowing.

[0046] In an optional embodiment of the present application, the blast furnace hydrogen-rich gas blowing hearth heat control method further comprises: if the opened multiple tuyeres 102 are switched to the state of stopping blowing, another tuyere 102 opposite to the tuyere 102 in the state of stopping blowing on the circumference of the furnace shell 1 is switched from the state of opening to the state of stopping blowing. In actual working process, when one tuyere 102 in the multiple tuyeres 102 stops blowing due to failure, another tuyere 102 opposite to the tuyere 102 on the circumference needs to be immediately stopped for blowing to avoid the uneven distribution of heat on the circumference of the hearth, ensure the smooth operation of the hearth and improve the output of the blast furnace.

[0047] Further, in the blast furnace hydrogen-rich gas blowing hearth heat control method of the present application, an interlocking program can be provided to associate any two tuyeres 102 opposite to each other on the circumference of the furnace shell 1, so that the two tuyeres 102 have the same working state. Specifically, the interlocking program can be used to synchronously control the start-stop state of the two tuyeres 102 for blowing the hydrogen-rich gas (such as synchronously controlling the on-off valves arranged at the two tuyeres 102 or synchronously controlling the working state of the supply device for supplying the hydrogen-rich gas to the two tuyeres 102), so as to achieve the purpose of interlocking control of the two tuyeres 102. The interlocking program can be the existing control program which can achieve the purpose of interlocking control, and is not limited.

[0048] In an optional embodiment of the present invention, when four tuyeres 102 evenly distributed around the circumference of the furnace shell are simultaneously opened for a first preset time to inject hydrogen-rich gas, or when multiple tuyeres 102 spaced apart around the circumference of the furnace shell are simultaneously opened for a first preset time to inject hydrogen-rich gas, the tuyeres 102 in the open state are controlled to switch to the off state, and the tuyeres 102 in the off state are controlled to switch to the off state, thereby making the hydrogen-rich gas injected axially upward in the furnace cylinder more uniform and achieving a better heat uniformity distribution effect. The first preset time can be adjusted and is not limited here.

[0049] In this invention, a corresponding hydrogen-rich gas spray gun is provided at each air outlet 102. The opening and stopping of the air outlet 102 are actually the spraying and stopping of hydrogen-rich gas by the hydrogen-rich gas spray gun at the corresponding air outlet 102.

[0050] In an optional embodiment of the present invention, when the tapping port 101 continues to tap iron for a second preset time, the tapping port 101 in the tapping state is controlled to switch to the stopped tapping state, and the tapping port 101 in the stopped tapping state is controlled to switch back to the tapping state. This method achieves alternating tapping operations for each tapping port 101, reducing the probability of continuous tapping accidents caused by a single tapping port 101 and avoiding long-term continuous tapping from a single tapping port 101. The second preset time can be adjusted and is not limited here.

[0051] Furthermore, an alternating tapping method can be adopted, where two opposing tapping ports 101 tap alternately, i.e. Figures 1 to 3 As shown, iron can be discharged synchronously at tap 1 and tap 3 for a second preset time. After that, tap 1 and tap 3 will stop discharging iron synchronously, and tap 2 and tap 4 will start discharging iron alternately. After the second preset time, tap 2 and tap 4 will stop discharging iron synchronously, and tap 1 and tap 3 will start discharging iron alternately.

[0052] In an optional embodiment of the present invention, when the amount of hydrogen-rich gas injected into the furnace hearth by the tuyeres 102 is reduced or stopped, the amount of hydrogen-rich gas injected by all the tuyeres 102 that are in the open state is changed in the same way. This ensures that the gas injected around the furnace hearth is always the same, thereby making the hydrogen-rich gas injected along the furnace hearth axis more uniform and achieving a better effect of uniform heat distribution.

[0053] In an optional embodiment of the present application, if the tuyere 102 sprays the mixture of hydrogen-rich gas and pulverized coal into the hearth, when the spraying amount of hydrogen-rich gas is reduced or stopped, the spraying amount of pulverized coal needs to be increased correspondingly, and the spraying amount of hydrogen-rich gas of all tuyeres 102 in the open state is changed uniformly. The purpose of increasing the spraying amount of pulverized coal is to make up for the heat loss caused by reducing the hydrogen-rich gas or stopping the spraying, so as to achieve the effect of making up heat and ensure the smooth operation of the blast furnace.

[0054] In the present application, the blast furnace can be a blast furnace with a volume of 350m 3 -6000m 3 In the present application, the blast furnace can be a blast furnace with a volume of 350m Figures 1 to 3 The number of tuyeres 102 can be, but is not limited to, 28 (i.e. 1# tuyere to 28# tuyere in the above table), and the number of tapholes 101 can be, but is not limited to, 4 (i.e. 1# taphole to 4# taphole in the above table), which is also applicable to a blast furnace with 2 tapholes or more than 4 tapholes. Figures 1 to 3 The number of tuyeres 102 can be, but is not limited to, 28 (i.e. 1# tuyere to 28# tuyere in the above table), and the number of tapholes 101 can be, but is not limited to, 4 (i.e. 1# taphole to 4# taphole in the above table), which is also applicable to a blast furnace with 2 tapholes or more than 4 tapholes.

[0055] In the present application, the blast furnace can be, but is not limited to, a hydrogen-rich smelting blast furnace, and also includes a blast furnace for spraying natural gas, coke oven gas, coal bed gas, blast furnace gas, converter gas, coal gas and the like.

[0056] The blast furnace hydrogen-rich gas spraying hearth heat control method of the present application has the following characteristics and advantages:

[0057] I. The blast furnace hydrogen-rich gas spraying hearth heat control method can avoid the uneven circumferential heat distribution of the blast furnace caused by the local theoretical combustion temperature drop in the hydrogen-rich gas smelting process, and can maximize the uniformity of the circumferential heat distribution of the blast furnace.

[0058] II. In the blast furnace hydrogen-rich gas spraying hearth heat control method, the positions of the tuyeres 102 and the tapholes 101 are staggered, which can reduce the theoretical combustion temperature drop in the local area of the taphole 102 or near the taphole 102, and further avoid the phenomenon of slag and iron removal obstruction caused by heat reduction, and ensure the complete removal of slag and iron.

[0059] The above description is only a specific embodiment of the present application, and is not intended to limit the scope of the present application. Any equivalent changes and modifications made by those skilled in the art without departing from the concept and principles of the present application shall fall within the scope of the present application.

Claims

1. A method for controlling heat in a blast furnace hearth by injecting a hydrogen-rich gas into the blast furnace, characterized by, The blast furnace comprises a furnace shell, at least four tapping holes and at least four tuyeres are arranged on the furnace shell, the plurality of tapping holes are evenly arranged along the circumference of the furnace shell, and the plurality of tuyeres are evenly arranged along the circumference of the furnace shell. The blast furnace hydrogen-rich gas injection hearth heat control method comprises the following steps: If the ton iron injection amount is less than a first preset value, the four tuyeres evenly distributed in the circumference of the furnace shell are synchronously opened to inject hydrogen-rich gas. If the ton iron injection amount is greater than or equal to the first preset value and less than or equal to a second preset value, the plurality of tuyeres spaced apart in the circumference of the furnace shell are synchronously opened to inject hydrogen-rich gas, and the number of the tuyeres synchronously opened is more than four. If the ton iron injection amount is greater than the second preset value, all the tuyeres in the circumference of the furnace shell are synchronously opened to inject hydrogen-rich gas, and the number of the tuyeres synchronously opened is more than four.

2. The blast furnace hydrogen-rich gas injection hearth heat control method as claimed in claim 1, characterized by, The furnace shell is in a cylindrical structure, the furnace shell is annularly arranged along the circumference to form a hearth, and the tapping holes and the tuyeres are staggered.

3. The blast furnace hydrogen-rich gas injection hearth heat control method as claimed in claim 2, characterized by, The plurality of tapping holes are located on a first plane, and the plurality of tuyeres are located on a second plane which is above the first plane.

4. The blast furnace hydrogen-rich gas injection hearth heat control method as claimed in claim 3, characterized by, When the four tuyeres evenly distributed in the circumference of the furnace shell are synchronously opened to inject hydrogen-rich gas, or when the plurality of tuyeres spaced apart in the circumference of the furnace shell are synchronously opened to inject hydrogen-rich gas, the tuyere directly above the tapping hole or the tuyere vertically adjacent to the tapping hole is in a stop-injection state.

5. The blast furnace hydrogen-rich gas injection hearth heat control method according to any one of claims 1 to 4, characterized by, The first preset value is 10 kg / ton iron, and / or the second preset value is 20 kg / ton iron.

6. The blast furnace hydrogen-rich gas injection hearth heat control method of claim 1, wherein, The blast furnace hydrogen-rich gas injection hearth heat control method further comprises the following steps: If the plurality of tuyeres opened are changed to a stop-injection state, another tuyere opposite to the stop-injection tuyere in the circumference of the furnace shell is changed from an opened state to a stop-injection state.

7. The blast furnace hydrogen-rich gas injection hearth heat control method as claimed in claim 6, characterized by, In the blast furnace hydrogen-rich gas injection hearth heat control method, an interlocking program is arranged, which is used to associate any two tuyeres opposite to each other in the circumference of the furnace shell, so that the two tuyeres have the same working state.

8. The blast furnace hydrogen-rich gas injection hearth heat control method of claim 1, wherein, When the tapping hole continuously taps iron for a second preset time, the tapping hole in the tapping state is controlled to change to a stop-tapping state, and the tapping hole in the stop-tapping state is controlled to change to a tapping state.

9. The blast furnace hydrogen-rich gas injection hearth heat control method of claim 2, wherein, When the injection amount of hydrogen-rich gas injected into the hearth by the tuyere is reduced or stopped, the injection amount of hydrogen-rich gas of all the tuyeres in the opened state is changed in the same way.

10. The blast furnace hydrogen-rich gas injection hearth heat control method as claimed in claim 9, characterized by, If the tuyere injects a mixture of hydrogen-rich gas and coal powder into the hearth, when the injection amount of hydrogen-rich gas is reduced or stopped, the injection amount of coal powder is increased correspondingly, and the injection amount of hydrogen-rich gas of all the tuyeres in the opened state is changed in the same way.

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