Furnace bottom structure of direct current submerged arc furnace and direct current submerged arc furnace

Abstract

The direct-current submerged arc furnace bottom structure comprises an electrode body, an air inlet groove and an air outlet groove which are arranged in parallel in the length direction of the electrode body are formed in the surface of the bottom of the electrode body and do not penetrate through the electrode body, and a communicating groove communicated with the air inlet groove and the air outlet groove is formed in one end of the air inlet groove and one end of the air outlet groove. Low-temperature air is directly conveyed to the furnace bottom through the air inlet groove and then discharged through the air outlet groove, and therefore the furnace bottom is cooled. During use, the ventilation performance of air entering the furnace bottom is better, and the furnace bottom can be better cooled; an air tunnel does not need to be independently formed in the furnace bottom of the submerged arc furnace, the integrity of the furnace bottom is guaranteed, and potential safety hazards of molten iron permeation are reduced.

Description

Technical Field

[0001] The invention relates to the technical field of direct current ore-fired furnaces, and in particular to a direct current ore-fired furnace bottom structure and a direct current ore-fired furnace. Background Art

[0002] The DC furnace bottom electrode has a high temperature due to the anode effect, which will form a hot furnace bottom. Although a hot furnace bottom is good for smelting, it puts higher requirements on the bottom electrode. General metal electrodes cannot be used due to the limitation of high temperature melting, so in recent years they have been replaced by graphite electrodes with good conductivity. However, graphite electrodes have good conductivity and thermal conductivity, and will transfer the high temperature in the furnace to the refractory bricks at the bottom of the furnace. When the load softening point of the refractory bricks is reached, the furnace bottom will crack. Therefore, the DC furnace bottom electrode needs to be cooled. There are currently two ways to cool it, one is air cooling and the other is water cooling. Because water cooling has a greater risk, graphite bottom electrodes are mostly cooled by air.

[0003] For example, the invention patent with the announcement number CN220524673U discloses a furnace bottom structure of an ore-heating furnace, in which a plurality of blind cooling holes are opened in the circumferential direction on the side wall of the furnace bottom of the ore-heating furnace, and the plurality of blind cooling holes are arranged in a radial shape along the center of the furnace bottom of the ore-heating furnace; a ventilation pipe is inserted into each blind cooling hole, and the outer diameter of the ventilation pipe is smaller than the inner diameter of the blind cooling hole; the outer end of the ventilation pipe is connected to the air supply pipe. The cooling air is sent into the blind cooling hole of the furnace bottom of the ore-heating furnace through the ventilation pipe, and then the heat of the furnace bottom of the ore-heating furnace is absorbed and then discharged from the blind cooling hole, thereby controlling the temperature of the furnace bottom of the ore-heating furnace within a certain range. However, when the above technical solution is used, since the ventilation pipe is built into the blind cooling hole, the air flow direction delivered by the ventilation pipe to the blind cooling hole needs to be turned 180° before it can be discharged along the gap between the blind cooling hole and the ventilation pipe, which is more likely to slow down the air flow rate, resulting in a decrease in air fluidity and affecting the cooling effect. In addition, the above scheme requires opening a wind tunnel at the bottom of the ore-fired furnace, which destroys the integrity of the furnace bottom and provides a channel for molten iron to penetrate, posing certain safety hazards. In addition, the masonry requirements for opening the wind tunnel are relatively high, and the cost of building the furnace is also high. Summary of the invention

[0004] In order to solve the technical problems existing in the above-mentioned technology, it is necessary to provide a direct current ore-fired furnace bottom structure.

[0005] A direct current ore-fired furnace bottom structure comprises an electrode body and a furnace bottom carbon brick layer; a blind hole is provided inside the furnace bottom carbon brick layer, the electrode body is installed in the blind hole, an air inlet groove and an air outlet groove are provided on the bottom surface of the electrode body and are arranged in parallel along the length direction of the electrode body, the air inlet groove and the air outlet groove do not penetrate the electrode body, a connecting groove connecting the air inlet groove and the air outlet groove is provided at one end of the air inlet groove and the air outlet groove, the connecting end of the air inlet groove and the air outlet groove is located at the bottom of the blind hole, so that an air inlet cavity and an air outlet cavity are formed between the air inlet groove and the air outlet groove on the electrode body and the blind hole.

[0006] Preferably, the depth of the air inlet groove, the air outlet groove, and the connecting groove is half of the height of the electrode body.

[0007] Preferably, the width of the air inlet groove, the air outlet groove, and the connecting groove is one quarter of the width of the electrode body.

[0008] Preferably, the blind holes are evenly distributed along the circumference of the center of the furnace bottom.

[0009] Preferably, a highly conductive carbon block is used between the ends of two opposite blind holes.

[0010] Preferably, a low-conductive carbon block is used between two adjacent blind holes.

[0011] Preferably, the highly conductive carbon block is built by conductive carbon bricks, and adjacent conductive carbon bricks are filled with graphite cold-rammed paste.

[0012] Preferably, the low-conductivity carbon blocks are built by thermal insulation carbon blocks, and the space between adjacent thermal insulation carbon blocks is filled with low thermal conductivity cold ramming paste.

[0013] It is also necessary to provide a direct current ore-fired furnace.

[0014] A DC ore-fired furnace comprises the DC ore-fired furnace bottom structure described above and a furnace body installed on the DC ore-fired furnace bottom structure.

[0015] Compared with the prior art, the DC ore-fired furnace bottom structure and the DC ore-fired furnace provided by the present invention provide air inlet grooves and air outlet grooves arranged in parallel on the electrode body, and the air inlet grooves and air outlet grooves are connected through the connecting grooves, and low-temperature air can be directly transported to the furnace bottom through the air inlet grooves and then discharged from the air outlet grooves, thereby realizing cooling of the furnace bottom. When the present invention is used, the air flowability entering the furnace bottom is better, which is more conducive to cooling the furnace bottom; there is no need to open a separate wind tunnel at the furnace bottom of the ore-fired furnace, which ensures the integrity of the furnace bottom and reduces the safety hazard of molten iron penetration. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for describing the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0017] Figure 1 It is a structural schematic diagram of the bottom structure of the direct current ore-fired furnace of the present invention.

[0018] Figure 2 For the present invention Figure 1 Schematic diagram of the side structure.

[0019] Figure 3 For the present invention Figure 1 Schematic diagram of the cross-sectional structure.

[0020] Figure 4 For the present invention Figure 1 Schematic diagram of the top view structure.

[0021] Figure 5 The schematic diagram of the structure of the bottom electrode of the DC smelting furnace of the present invention.

[0022] Figure 6 For the present invention Figure 5 Schematic diagram of the structure from another angle.

[0023] In the figure: electrode body 01, air inlet groove 11, air outlet groove 12, connecting groove 13, furnace bottom carbon brick layer 02, blind hole 21, air inlet cavity 22, and air outlet cavity 23. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] In the description of the present invention, it should be understood that the terms "upper", "middle", "outer", "inner", "lower" and the like indicating directions or positional relationships are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the components or elements referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as limiting the present invention.

[0026] Please see Figures 1 to 6In one embodiment, the present invention provides a DC ore furnace bottom structure, including an electrode body 01 and a furnace bottom carbon brick layer 02; a blind hole 21 is provided inside the furnace bottom carbon brick layer 02, and the electrode body 01 is installed in the blind hole 21. An air inlet groove 11 and an air outlet groove 12 are provided on the bottom surface of the electrode body 01 and are arranged in parallel along the length direction of the electrode body 01. The air inlet groove 11 and the air outlet groove 12 do not penetrate the electrode body 01, and a connecting groove 13 connecting the air inlet groove 11 and the air outlet groove 12 is provided at one end of the air inlet groove 11 and the air outlet groove 12. Of course, in order to make the air flow better, the connecting groove 13 can adopt an arc structure. When the air inlet groove 11 and the air outlet groove 12 are connected through the connecting groove 13, the air inlet groove 11, the air outlet groove 12, and the connecting groove 13 form a U-shaped path. Among them, the diameter of the connecting groove 13 is the distance between the air inlet groove 11 and the air outlet groove 12. The connecting ends of the air inlet groove 11 and the air outlet groove 12 are located at the bottom of the blind hole 21, so that an air inlet cavity 22 and an air outlet cavity 23 are formed between the air inlet groove 11 and the air outlet groove 12 on the electrode body 01 and the blind hole 21. The air inlet cavity 22 can be connected to the air supply equipment, so that low-temperature air is sent to the furnace bottom through the air inlet cavity 22. After passing through the furnace bottom, the low-temperature air exchanges heat with the furnace bottom and is discharged through the air outlet cavity 23, thereby effectively cooling the furnace bottom.

[0027] Specifically, the depths of the air inlet groove 11 , the air outlet groove 12 , and the connecting groove 13 are half of the height of the electrode body 01 .

[0028] Specifically, the width of the air inlet groove 11 , the air outlet groove 12 , and the connecting groove 13 is one quarter of the width of the electrode body 01 .

[0029] The blind holes 21 are evenly distributed along the circumference of the center of the furnace bottom.

[0030] A highly conductive carbon block is used between the ends of the two opposite blind holes 21, which can guide the current to flow to the bottom electrode, reduce the bias current phenomenon, and improve the conductivity efficiency of the DC furnace. The highly conductive carbon block is made of conductive carbon bricks, and graphite cold ramming paste is used to fill the adjacent conductive carbon bricks.

[0031] The indicators of conductive carbon bricks and graphite cold ramming paste are shown in the following table:

[0032] Among them, low-conductivity carbon blocks are used between two adjacent blind holes 21, which can protect the refractory bricks at the bottom of the furnace. Among them, the low-conductivity carbon blocks are built by thermal insulation carbon blocks, and low-thermal conductivity cold ramming paste is used to fill the gaps between adjacent thermal insulation carbon blocks.

[0033] The indicators of thermal insulation carbon blocks and low thermal conductivity cold ramming paste are shown in the following table:

[0034] In one embodiment, the present invention provides a DC ore-fired furnace, including a furnace bottom structure of the DC ore-fired furnace and a furnace body installed on the furnace bottom structure of the DC ore-fired furnace.

[0035] What is disclosed above is only a preferred embodiment of the present invention, which certainly cannot be used to limit the scope of rights of the present invention. A person skilled in the art can understand that all or part of the processes of the above embodiments and equivalent changes made according to the claims of the present invention still fall within the scope of the invention.

Claims

1. A DC ore-fired furnace bottom structure, characterized in that: It includes an electrode body and a furnace bottom carbon brick layer; a blind hole is opened inside the furnace bottom carbon brick layer, the electrode body is installed in the blind hole, and an air inlet groove and an air outlet groove are opened on the bottom surface of the electrode body and are arranged in parallel along the length direction of the electrode body. The air inlet groove and the air outlet groove do not penetrate the electrode body, and a connecting groove connecting the air inlet groove and the air outlet groove is arranged at one end of the air inlet groove and the air outlet groove. The connecting end of the air inlet groove and the air outlet groove is located at the bottom of the blind hole, so that an air inlet cavity and an air outlet cavity are formed between the air inlet groove and the air outlet groove on the electrode body and the blind hole.

2. The DC ore-fired furnace bottom structure according to claim 1 is characterized in that: The depths of the air inlet groove, the air outlet groove, and the connecting groove are half of the height of the electrode body.

3. The DC ore-fired furnace bottom structure according to claim 2 is characterized in that: The width of the air inlet groove, the air outlet groove and the connecting groove is one quarter of the width of the electrode body.

4. The DC ore-fired furnace bottom structure according to claim 1, characterized in that: The blind holes are evenly distributed along the circumference of the center of the furnace bottom.

5. The DC ore-fired furnace bottom structure according to claim 4 is characterized in that: A highly conductive carbon block is used between the ends of two opposing blind holes.

6. The DC ore-fired furnace bottom structure according to claim 5, characterized in that: A low-conductive carbon block is used between two adjacent blind holes.

7. The DC ore-fired furnace bottom structure according to claim 5, characterized in that: The high-conductivity carbon block is built by conductive carbon bricks, and graphite cold-rammed paste is used to fill the space between adjacent conductive carbon bricks.

8. The DC ore-fired furnace bottom structure according to claim 6, characterized in that: The low-conductivity carbon blocks are built by building up heat-insulating carbon blocks, and low-thermal-conductivity cold-rammed paste is used to fill the spaces between adjacent heat-insulating carbon blocks.

9. A DC ore-fired furnace, characterized in that: It comprises the DC ore-fired furnace bottom structure as claimed in any one of claims 1 to 8, and a furnace body installed on the DC ore-fired furnace bottom structure.

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