Shaft furnace device with air entering from center

Abstract

The utility model belongs to the technical field of low-carbon metallurgy, and relates to a central air inlet shaft furnace device which comprises a shaft furnace body, a reducing gas main pipe, a reducing gas bypass, a first stop valve, a second stop valve, a valve front central air inlet pipe, a central air inlet pipe, a central air inlet distributor and an eduction pipe, the reducing gas main pipe is connected to the side part of the shaft furnace body; the reducing gas bypass is arranged on the reducing gas main pipe and is communicated with the central gas inlet pipe through a first stop valve; the valve front central air inlet pipe is connected to the central air inlet pipe through a second stop valve; and the central air inlet pipe extends into the shaft furnace body and is communicated with the central air inlet distributor. According to the utility model, a stream of reducing gas or other gas is introduced into the center of the shaft furnace to change the distribution of gas entering the furnace in the center of the shaft furnace, so that the gas flow distribution of the whole section is uniform, thereby improving the reaction between the reducing gas and pellets and improving the metallization ratio.

Description

TECHNICAL FIELD

[0001] The utility model belongs to low carbon metallurgical technical field relates to a center air inlet's shaft furnace device. BACKGROUND

[0002] With the aggravation of global environmental problems, green low carbon metallurgy has become an important development direction of the steel industry. As a representative process of realizing low carbon metallurgy, gas-based shaft furnace significantly reduces carbon dioxide emissions by using hydrogen or natural gas as reducing gas instead of traditional coke. The core of this process is the efficient reaction of reducing gas and iron-containing raw materials (such as pellets) in the shaft furnace to produce direct reduced iron (DRI). However, there are still key technical bottlenecks in the practical application of traditional gas-based shaft furnace, which are as follows:

[0003] 1. Inherent defect of uneven distribution of reducing gas

[0004] Traditional shaft furnace usually adopts a circumferential air inlet structure, and reducing gas is uniformly injected into the furnace through annular pipes on the side wall or top. However, due to the difference in gas flow characteristics of the radial cross section of the shaft furnace, high-speed airflow is easily formed near the wall, while the flow rate in the central region is significantly reduced due to the large gas diffusion resistance, resulting in a "central dead zone". The contact efficiency of reducing gas and pellets in this area is low, the reaction is not sufficient, and finally the overall metallization rate of the shaft furnace is low (usually less than 92%) and the product quality is unstable.

[0005] 2. Limitations of existing optimization techniques

[0006] In order to improve the gas flow distribution, the industry has tried to improve the air inlet structure, such as adding multiple air inlets or adjusting the pipe layout. However, these solutions are often difficult to industrialize due to their complex structure and high adjustment difficulty. In addition, relying solely on external gas flow distribution devices cannot completely solve the "weak flow" problem in the central region, and may even exacerbate the flow field turbulence in the furnace due to gas flow interference.

[0007] 3. Conflict between process efficiency and low carbon target

[0008] In traditional shaft furnaces, in order to compensate for the insufficient reaction in the central region, the total amount of reducing gas or its temperature needs to be increased, resulting in increased energy consumption and increased carbon emissions. This contradiction seriously restricts the competitiveness of gas-based shaft furnaces in low carbon metallurgy.

[0009] Therefore, there is an urgent need for a new structural design that can optimize the internal gas flow distribution of the shaft furnace and enhance the reaction efficiency in the central region. SUMMARY

[0010] Therefore, the purpose of the utility model is to provide a center air inlet's shaft furnace device, by introducing a reducing gas in the center of the shaft furnace, changing the distribution of the reducing gas in the center of the shaft furnace, thereby improving the reaction of the reducing gas and the pellets, and improving the metallization rate.

[0011] To achieve the above object, the utility model provides the following technical scheme: a vertical furnace device of central gas inlet, including vertical furnace body, reduction gas main pipe, reduction gas side branch, first cut -out valve, second cut -out valve, valve front central gas inlet pipe, central gas inlet pipe, central gas inlet distributor and lead -out pipe, the reduction gas main pipe is connected to the side portion of vertical furnace body, the reduction gas side branch is located on the reduction gas main pipe, and is communicated with the central gas inlet pipe through the first cut -out valve, the valve front central gas inlet pipe is connected to the central gas inlet pipe through the second cut -out valve, the central gas inlet pipe extends to the inside of vertical furnace body and is communicated with the central gas inlet distributor.

[0012] Optionally, the central gas inlet pipe is horizontally penetrated from the side portion of vertical furnace body and is vertically connected with the central gas inlet distributor.

[0013] Optionally, the central gas inlet pipe is vertically penetrated from the bottom of vertical furnace body, extends upward to the central axial area and is connected with the central gas inlet distributor.

[0014] Optionally, the central gas inlet pipe is communicated with the central gas inlet distributor and flows out through a plurality of through holes arranged on the upper portion of the central gas inlet distributor.

[0015] Optionally, the reduction gas entering the vertical furnace body is cold reduction gas or hot reduction gas.

[0016] Optionally, a part of the reduction gas participating in the reaction enters the vertical furnace through the reduction main pipe, and a part of the reduction gas enters the vertical furnace through the central gas inlet pipe.

[0017] Optionally, all the reduction gas participating in the reaction enters the vertical furnace through the reduction main pipe, and the central gas inlet enters the vertical furnace through the central gas inlet pipe.

[0018] The utility model discloses a vertical furnace device of central gas inlet, and its core innovation is to set specific gas introduction device in the central area of vertical furnace, introduce reduction gas or other specific gas and overturn the traditional gas distribution mode. The design realizes the uniform diffusion of airflow in the whole section of vertical furnace, ensures that reduction gas and pellet material are in full contact, makes reduction reaction uniform and efficient. Compared with the traditional mode, the uniform airflow distribution greatly improves the reaction efficiency of reduction gas and pellet, and each pellet can obtain sufficient gas supply, accelerates the reduction reaction. At the same time, the design effectively improves the smelting environment of vertical furnace, reduces the local overheating or reduction deficiency phenomenon and avoids smelting quality problems. In addition, the central gas inlet device also improves the overall operation stability of vertical furnace and prolongs the service life of equipment. Most importantly, the technology significantly improves the metallization rate, improves the smelting efficiency and reduces the production cost. The innovative technology injects new vitality into the vertical furnace smelting industry and has very high practical value and economic benefits, and is an important force to promote the development of the industry.

[0019] Other advantages, objects, and features of the present application will be apparent to those skilled in the art from the following specification, which is to be taken in conjunction with the accompanying drawings. The objects and other advantages of the present application can be realized and attained by the structure particularly pointed out in the specification and claims hereof as well as the appended drawings. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to make the purpose, technical scheme and advantages of the present application more clear, the preferred embodiments of the present application will be described in detail below with reference to the drawings, in which:

[0021] Figure 1 Fig. 1 is a structural schematic view of a specific embodiment 1 of the present application;

[0022] Figure 2 Fig. 2 is a structural schematic view of a specific embodiment 2 of the present application.

[0023] The drawings show: a shaft furnace body 1, a reducing gas main pipe 2, a reducing gas side branch 3, a first cut-off valve 4, a second cut-off valve 5, a valve front center gas inlet pipe 6, a center gas inlet pipe 7, a center gas inlet distributor 8, and a lead-out pipe 9. DETAILED DESCRIPTION

[0024] The embodiments of the present application will be described in detail below with reference to specific examples. Those skilled in the art can easily understand other advantages and effects of the present application from the content disclosed in the specification. The present application can also be implemented or applied in different specific embodiments, and the details in the specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that the drawings provided in the following examples only illustrate the basic concept of the present application in a schematic manner, and the features in the following examples and embodiments can be combined with each other without conflict.

[0025] The drawings are only used for illustrative explanation, and the representation is only a schematic diagram, not a physical drawing, and should not be understood as a limitation of the present application. In order to better illustrate the embodiments of the present application, some components in the drawings may be omitted, enlarged or reduced, and do not represent the actual product size. It is understandable for those skilled in the art that some known structures and their descriptions in the drawings may be omitted.

[0026] The same or similar reference signs in the drawings of the embodiments of the present application correspond to the same or similar components; in the description of the present application, it is understood that if the orientations or positional relationships indicated by the terms "upper", "lower", "left", "right", "front", "back" and the like are based on the orientations or positional relationships shown in the drawings, they are only for the convenience of describing the present application and simplifying the description, and therefore the terms describing the positional relationships in the drawings are only used for exemplary illustration and cannot be understood as limiting the present application, and for those skilled in the art, the specific meanings of the above terms can be understood according to specific circumstances. Specific embodiment 1

[0028] Please refer to Figure 1 It is a central gas inlet shaft furnace device, including shaft furnace body 1, reduction gas main pipe 2, reduction gas branch pipe 3, first cut-off valve 4, second cut-off valve 5, pre-valve central gas inlet pipe 6, central gas inlet pipe 7, central gas inlet distributor 8 and outlet pipe 9;The reduction gas main pipe 2 is connected to the side of the shaft furnace body 1;The reduction gas branch pipe 3 is arranged on the reduction gas main pipe 2 and communicates with the central gas inlet pipe 7 through the first cut-off valve 4;The pre-valve central gas inlet pipe 6 is connected to the central gas inlet pipe 7 through the second cut-off valve 5;The central gas inlet pipe 7 extends to the inside of the shaft furnace body 1 and communicates with the central gas inlet distributor 8;The central gas inlet distributor 8 is fixed to the central axial area of the shaft furnace body 1, the outlet pipe 9 is arranged at the top of the shaft furnace body 1, and the diameter of the reduction gas branch pipe 3 is smaller than that of the reduction gas main pipe 2.

[0029] In this embodiment, the reduction gas entering the shaft furnace body 1 is cold reduction gas or hot reduction gas, the central gas inlet distributor 8 is a reverse conical structure, the central gas inlet pipe 7 communicates with the lower part of the central gas inlet distributor 8, and flows out through a plurality of through holes uniformly arranged on the upper part of the central gas inlet distributor 8.

[0030] In this embodiment, the central gas inlet pipe 7 horizontally penetrates from the side of the shaft furnace body 1 and is connected perpendicularly with the central gas inlet distributor 8.

[0031] In use, the present embodiment includes two kinds of gas inlet modes:

[0032] (1) The reduction gas is introduced to the side of the shaft furnace body 1 through the reduction gas main pipe 2, a part of the reduction gas directly enters the inside of the shaft furnace body 1;Close the second cut-off valve 5 and open the first cut-off valve 4, a part of the reduction gas is introduced into the central gas inlet pipe 7 through the reduction gas branch pipe 3, and enters the shaft furnace body 1 through the central gas inlet pipe distributor 8, and the top gas after reacting with the pellets is discharged from the shaft furnace through the outlet pipe 9.

[0033] (2) Reducing gas is introduced to the side of the shaft furnace body 1 through the reducing gas main pipe 2, the first cut-off valve 4 is closed, and the reducing gas is directly introduced into the inside of the shaft furnace body 1; the second cut-off valve 5 is opened, and another part of the reducing gas is introduced into the center gas inlet pipe 7 through the valve front center gas inlet pipe 6 and the center gas inlet pipe distributor 8, and the top gas after reacting with the pellets is discharged from the shaft furnace through the discharge pipe 9. Specific embodiment 2

[0035] Different from specific embodiment 1, in this embodiment, the center gas inlet pipe 7 vertically penetrates from the bottom of the shaft furnace body 1, extends upward to the center axial area, and is connected with the center gas inlet distributor 8.

[0036] The difference between specific embodiments 1 and 2 is that the center gas inlet pipe 7 is connected in different ways according to different shaft furnace bodies 1. In specific embodiment 1, the center gas inlet pipe 7 is connected in a way of horizontally penetrating and vertically connecting with the center gas inlet distributor 8; while in specific embodiment 2, the center gas inlet pipe 7 is connected with the center gas inlet distributor 8 in a way of vertically penetrating from the bottom of the shaft furnace body 1 to adapt to the structure and needs of different shaft furnace bodies 1.

[0037] Finally, it should be pointed out that the above embodiments are only used to illustrate the technical solutions of the present application and are not limiting. Although the present application has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solutions of the present application can be modified or replaced equivalently without departing from the purpose and scope of the present application, and all should be covered in the scope of the claims of the present application.

Claims

1. A central gas inlet shaft furnace installation, characterized in that: The vertical furnace body, the reducing gas main pipe, the reducing gas branch pipe, the first cut-off valve, the second cut-off valve, the pre-valve central gas inlet pipe, the central gas inlet pipe, the central gas inlet distributor and the outlet pipe are included; the reducing gas main pipe is connected to the side of the vertical furnace body; the reducing gas branch pipe is arranged on the reducing gas main pipe and communicates with the central gas inlet pipe through the first cut-off valve; the pre-valve central gas inlet pipe is connected to the central gas inlet pipe through the second cut-off valve; the central gas inlet pipe extends to the inside of the vertical furnace body and communicates with the central gas inlet distributor.

2. A central gas entry shaft furnace apparatus according to claim 1, wherein: The central gas inlet pipe horizontally penetrates from the side of the vertical furnace body and vertically connects with the central gas inlet distributor.

3. A central gas entry shaft furnace apparatus according to claim 1, wherein: The central gas inlet pipe vertically penetrates from the bottom of the vertical furnace body, extends upward to the central axial area and communicates with the central gas inlet distributor.

4. A central gas entry shaft furnace apparatus according to claim 1, wherein: The central gas inlet pipe communicates with the central gas inlet distributor and flows out through a plurality of through holes arranged on the upper part of the central gas inlet distributor.

5. A central gas entry shaft furnace apparatus according to claim 1, wherein: The reducing gas entering the vertical furnace body is cold reducing gas or hot reducing gas.

6. A central gas entry shaft furnace apparatus according to claim 1, wherein: The reducing gas participating in the reaction enters the vertical furnace through the reducing main pipe and the central gas inlet pipe.

7. A central gas entry shaft furnace apparatus according to claim 1, wherein: The reducing gas participating in the reaction enters the vertical furnace through the reducing main pipe, and the central gas inlet enters the vertical furnace through the central gas inlet pipe. The reducing gas participating in the reaction enters the vertical furnace through the reducing main pipe, and the central gas inlet enters the vertical furnace through the central gas inlet pipe.

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