Burner structure of copper shaft furnace

Abstract

To provide a burner structure of a copper shaft furnace which makes re-solidified products of melted copper less likely to adhere to a burner tile.SOLUTION: A burner structure of a copper shaft furnace includes: a burner installed outside a copper shaft furnace; a burner tile in which an opening at one end side faces one end side of a furnace body flame introduction path to form a flame introduction path and which is installed at the furnace body of the furnace; and a flame holder which is inserted at one end side into the burner tile from the other end side of the burner tile, open in the burner tile flame introduction path, and connected at the other end side to the burner and which is provided with a flame introduction path for guiding flame jetted from the burner into the furnace and installed between the burner tile and the burner. The opening at the one end side of the flame holder is positioned at a position such that the high temperature part of the flame jetted from the burner can heat an area near the innermost position of the burner tile.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a burner structure installed in a shaft furnace for melting copper to heat the inside of the furnace. [Background technology]

[0002] In the manufacture of copper pipes, copper rods, copper wires, copper strips, etc., copper is melted to obtain copper ingots, which are then subjected to various processes to produce copper pipes, copper rods, copper wires, copper strips, etc. Shaft furnaces used for reduction melting of copper have traditionally been used to melt copper.

[0003] A copper shaft furnace is provided with a preheating zone, a melting zone, and a heating zone, in that order, from the top where the raw materials are supplied, to the bottom, and the raw materials to be melted, such as electrolytic copper, are supplied from the top. Inside the furnace, the raw materials to be melted are heated by burners installed on the furnace wall, and molten copper is produced at the bottom of the furnace. The molten copper is continuously removed from the furnace through a taphole at the bottom of the furnace and used to produce copper ingots.

[0004] In a copper shaft furnace, the raw material to be melted is heated by a burner installed on the furnace wall. Figure 3 shows an example of a conventional burner structure installed in the furnace body of the copper shaft furnace. In Figure 3, a burner structure 30 is installed in the furnace body 32 of the copper shaft furnace, and the burner structure 30 has at least a burner 33 installed outside the copper shaft furnace, a burner tile 34 installed in the furnace body 32 and with a frame holder 35 inserted inside, and a flame holder 35 installed between the burner tile 34 and the burner 33, one end of which is inserted inside the burner tile 34 and the other end of which is connected to the burner 33, and a flame introduction path 38 is formed on the inside to guide the flame ejected from the burner 33 to the furnace interior 31 of the copper shaft furnace.

[0005] In the burner structure 30 of the copper shaft furnace, fuel and a combustion-supporting gas such as air are supplied to the burner 33, and the fuel is burned at the tip of the burner 33 to generate a flame, which is introduced into the furnace interior 31 via the frame holder frame introduction path 38 and the furnace body frame introduction path 37. The flame introduced into the furnace interior 31 of the copper shaft furnace heats the melting raw material to produce molten copper.

[0006] As an example of a burner structure for a copper shaft furnace, Patent Document 1 discloses a combustion device that includes a main burner and a flame-holding burner that has the same central axis as the main burner and is arranged along the central axis of the main burner, the flame-holding burner including an aperture adjuster that adjusts the ejection speed of premixed gas ejected from the main burner, an ignition torch for igniting a flame, and a flame stabilizer that maintains and adjusts the flame stably, and the aperture adjuster, the position of the ignition torch in the central axial direction, and the flame-holding burner are all independently adjustable. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2006-242399 A Summary of the Invention [Problem to be solved by the invention]

[0008] However, in the conventional burner structure, there was a problem in that the re-solidified molten copper (reference number 39 in Figure 3) would adhere to the part inside the furnace from the innermost position on the other end of the furnace frame introduction path, causing clogging.

[0009] One possible method for suppressing the occurrence of re-solidified molten copper is to preheat the combustion-supporting gas in advance, thereby preventing the burner tile from being cooled by the combustion-supporting gas and suppressing the occurrence of re-solidified molten copper.

[0010] However, such a method requires the installation of a preheating device, which increases the equipment costs.

[0011] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a burner structure for a copper shaft furnace in which re-solidified molten copper is less likely to adhere to the furnace body. [Means for solving the problem]

[0012] Based on the above technical background, the inventors conducted extensive research and found that, whereas conventionally, in order to efficiently use the heat of the flame generated by the burner inside the furnace, the opening position of the flame holder in the direction of the central axis of the burner was set close to the inside of the furnace, conversely, by moving the opening position of the flame holder in the direction of the central axis of the burner a certain distance away from the inside of the furnace, it is possible to prevent the re-solidified molten copper from adhering to the portion of the burner tile closer to the inside of the furnace than its innermost position, and thus completed the present invention.

[0013] That is, the present invention (1) provides a burner that is installed outside a copper shaft furnace at a predetermined distance from the inner wall of the furnace so that an extension line of the central axis of the burner overlaps with the central axis of a furnace body frame introduction path formed in the furnace body of the furnace; A burner tile is installed in the furnace body of the furnace such that the opening on one end side faces one end side of the furnace body frame introduction path, the burner tile frame introduction path is formed to guide the flame emitted from the burner into the furnace, and the central axis of the burner tile frame introduction path overlaps with the extension line of the central axis of the burner; a flame holder having a flame holder frame introduction path formed therein, one end of which is inserted into the inside of the burner tile from the other end of the burner tile and opens into the burner tile frame introduction path, and the other end of which is connected to the burner and guides the flame emitted from the burner into the furnace, the flame holder being installed between the burner tile and the burner such that the central axis of the flame holder frame introduction path overlaps with an extension of the central axis of the burner; having an opening on one end side of the flame holder is positioned at a position where a high temperature part of the flame ejected from the burner can heat the vicinity of the innermost position of the burner tile; The present invention provides a burner structure for a copper shaft furnace, characterized in that

[0014] The present invention (2) also provides a burner structure for a copper shaft furnace according to (1), characterized in that the distance in the central axial direction of the burner from the innermost position on the other end side of the furnace body frame introduction path to one end of the frame holder is 210 to 280 mm.

[0015] The present invention (3) also provides a burner structure for a copper shaft furnace according to (1), characterized in that the angle θ between a straight line passing through the innermost position of the other end of the furnace body frame introduction path and the innermost position of one end of the frame holder and the central axis of the burner is 5 to 8°. Effect of the Invention

[0016] According to the present invention, it is possible to provide a burner structure for a copper shaft furnace in which re-solidified molten copper is less likely to adhere to the furnace body. [Brief description of the drawings]

[0017] [Figure 1] FIG. 2 is a schematic end view of an example embodiment of a burner structure for a copper shaft furnace of the present invention. [Diagram 2] FIG. 2 is a schematic end view of another embodiment of the burner structure of the copper shaft furnace of the present invention. [Diagram 3] FIG. 1 is a schematic end view of an example of a burner structure for a conventional copper shaft furnace. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] The burner structure of the copper shaft furnace of the present invention is a burner that is installed outside the copper shaft furnace at a predetermined distance from the inner wall of the furnace so that an extension line of the central axis of the burner overlaps with the central axis of the furnace body frame introduction path formed in the furnace body of the furnace; A burner tile is installed in the furnace body of the furnace such that the opening on one end side faces one end side of the furnace body frame introduction path, the burner tile frame introduction path is formed to guide the flame emitted from the burner into the furnace, and the central axis of the burner tile frame introduction path overlaps with the extension line of the central axis of the burner; a flame holder having a flame holder frame introduction path formed therein, one end of which is inserted into the inside of the burner tile from the other end of the burner tile and opens into the burner tile frame introduction path, and the other end of which is connected to the burner and guides the flame emitted from the burner into the furnace, the flame holder being installed between the burner tile and the burner such that the central axis of the flame holder frame introduction path overlaps with an extension of the central axis of the burner; having The opening on one end side of the frame holder is positioned at a position where the high temperature part of the flame ejected from the burner can heat the vicinity of the innermost position on the other end side of the furnace body frame introduction path. It is characterized by:

[0019] The burner structure of the copper shaft furnace of the present invention will be described with reference to FIG. 1. FIG. 1 is a schematic end view of an embodiment of the burner structure of the copper shaft furnace of the present invention, and is an end view when cut along a plane overlapping the central axis of the burner. In FIG. 1, a burner structure 10a is installed in the furnace body 2 of the copper shaft furnace, and the burner structure 10a has at least a burner 3, a burner tile 4, and a frame holder 5. The furnace body 2 is formed with a furnace body frame introduction path 14. The burner tile 4 is formed with a burner tile frame introduction path 7 that guides the flame ejected from the burner 3 to the furnace interior 1 of the copper shaft furnace. The burner tile 4 is installed in the furnace body 2 of the copper shaft furnace, and one end side opens to one end side of the furnace body frame introduction path 14 of the copper shaft furnace. The frame holder 5 is formed with a frame holder frame introduction path 8 that guides the flame ejected from the burner 3 to the furnace interior 1 of the copper shaft furnace. One end of the frame holder 5 is inserted inside the burner tile 4 and opens into the burner tile frame introduction path 7, and the other end is connected to the burner 3. The frame holder 5 is inserted into the burner tile frame introduction path 7 and connected to the burner 3, and is installed between them, so that the burner 3 is installed outside the furnace at a predetermined distance from the inner wall 13 of the copper shaft furnace. At this time, the frame holder 5 is installed so that the central axis of the frame holder 5 overlaps with the extension line 11 of the central axis of the burner, and the central axis of the burner tile 4 is also installed so that it generally overlaps with the extension line 11 of the central axis of the burner.

[0020] In the burner structure 10a of the copper shaft furnace, fuel gas and combustion-supporting gas such as air are supplied to the burner 3, and the fuel burns at the tip of the burner 3 to generate a flame, which is introduced into the furnace interior 1 via the frame holder frame introduction path 8, the burner tile frame introduction path 7, and the furnace body frame introduction path 14. The flame introduced into the furnace interior 1 of the copper shaft furnace heats the melting raw material, producing molten copper.

[0021] In Fig. 1, the innermost position 6 on the other end side of the furnace frame introduction path 14 refers to the innermost position (the position closest to the central axis) when the furnace frame introduction path is viewed in the radial direction (on a surface perpendicular to the central axis). In Fig. 1, which is an end view cut along a plane including an extension line 11 of the central axis of the burner 3, it refers to the position closest to the extension line 11 of the central axis of the burner 3 on the other end side of the furnace frame introduction path 14. In addition, the distance X from the innermost position on the other end side of the furnace frame introduction path 14 to one end of the frame holder in the central axis direction of the burner refers to the distance between the line connecting the innermost position 6 on the other end side of the furnace frame introduction path 14 and the line connecting the innermost position 9 at one end of the frame holder in Fig. 1. In addition, in Figure 1, the straight line 12 passing through the innermost position 6 on the other end side of the furnace frame introduction path 14 and the innermost position 9 on one end of the frame holder refers to the straight line passing through the innermost position 6 on the other end side of the furnace frame introduction path 14 and the innermost position 9 on one end of the frame holder, and the angle θ between the straight line 12 and the central axis of the burner refers to the angle between the straight line 12 and an extension line 11 of the central axis of the burner 3 in Figure 1.

[0022] The burner structure of the copper shaft furnace of the present invention may have a horizontal center line of the burner as in the embodiment shown in FIG. 1, or may have a center line of the burner inclined to the horizontal direction as in the embodiment shown in FIG. 2. FIG. 2 is a schematic end view of another embodiment of the burner structure of the copper shaft furnace of the present invention. In FIG. 2, in the burner structure 10b of the copper shaft furnace, the center line 11 of the burner is inclined to the horizontal direction so that the burner frame jets out obliquely downward. In addition, the burner structure 10b of the copper shaft furnace is the same as the burner structure 10a of the copper shaft furnace in FIG. 1, except that the center line of the burner is inclined to the horizontal direction.

[0023] The burner is a component that supplies and mixes fuel gas such as city gas and combustion-supporting gas such as air or oxygen gas, and discharges the mixed gas toward the inside of the furnace in order to burn the fuel gas and generate a flame. The fuel gas burns at the tip of the burner, generating a flame whose tip faces the inside of the copper shaft furnace.

[0024] The burner is installed in the furnace body of the copper shaft furnace via a burner tile and a frame holder, so that the burner is installed outside the furnace at a predetermined distance from the inner wall of the copper shaft furnace.

[0025] The diameter of the opening at the tip of the burner is not particularly limited, but is usually 30 to 100 mm.

[0026] The flame holder is a component installed between the burner and the burner tile, with one end inserted into the burner tile frame introduction path from the other end of the burner tile and fixed to the other end of the burner tile, and the other end connected and fixed to the tip of the burner.

[0027] The flame holder has a flame holder frame introduction passage formed on the inside thereof for guiding the flame ejected from the burner into the copper shaft furnace. An opening on one end of the flame holder opens in the burner tile frame introduction passage on the inside of the burner tile, and an opening on the other end faces the opening at the tip of the burner.

[0028] The diameter of the opening at one end of the flame holder is not particularly limited, but is usually 30 to 100 mm, and the diameter of the opening at the other end of the flame holder is usually approximately the same as the diameter of the opening at the tip of the burner.

[0029] The frame holder frame introduction path formed inside the frame holder has a cross-sectional shape perpendicular to the central axis that is substantially circular.

[0030] The material of the frame holder is not particularly limited, and examples thereof include SiC bricks.

[0031] The burner tile is a member that is installed in the furnace body of the copper shaft furnace by being fixed to the furnace body so that an opening on one end side of the burner tile faces one end side of the furnace body frame introduction path formed in the furnace body of the copper shaft furnace. In other words, the burner tile is a member that is directly fixed to the furnace body of the copper shaft furnace in order to install the burner structure of the present invention in the copper shaft furnace.

[0032] The burner tile has a burner tile frame introduction passage formed on the inside thereof to guide the flame emitted from the burner into the copper shaft furnace. An opening on one end of the burner tile faces one end of the furnace frame introduction passage, and one end of the flame holder is inserted inside the other end.

[0033] The shape of a cross section perpendicular to the central axis of the burner tile frame introduction passage formed inside the burner tile is approximately circular.

[0034] The material of the burner tile is not particularly limited, and examples thereof include SiC bricks.

[0035] In the burner structure of the present invention, the flame holder is installed so that the central axis of the flame holder frame introduction path substantially overlaps with the extension line of the central axis of the burner, and the burner tile is installed so that the central axis of the burner tile frame introduction path substantially overlaps with the extension line of the central axis of the burner. Note that in the burner structure of the present invention, it is sufficient that the central axis of the frame introduction path of the flame holder or burner tile substantially overlaps with the extension line of the central axis of the burner, and the central axis of the frame introduction path of the flame holder or burner tile substantially overlaps with the extension line of the central axis of the burner includes the case where the central axis of the frame introduction path of the flame holder or burner tile completely overlaps with the extension line of the central axis of the burner, and the case where the central axis of the frame introduction path of the flame holder or burner tile is slightly deviated from the extension line of the central axis of the burner within a range that does not impair the effects of the present invention.

[0036] In the burner structure of the present invention, the opening on one end of the frame holder is positioned at a position where the high temperature part of the flame spewing from the burner can heat the vicinity of the innermost position on the other end of the furnace frame introduction path. In the conventional burner structure, the opening position of the frame holder is designed to be close to the inside of the furnace in order to efficiently use the heat of the flame generated by the burner in the furnace. However, the inventors have found that, on the contrary, the opening position of the frame holder is positioned in a direction away from the inside of the furnace, and the high temperature part of the flame spewing from the burner is positioned near the innermost position on the other end of the furnace frame introduction path or in a position overlapping with the innermost position on the other end of the furnace frame introduction path, thereby making it difficult for the resolidified molten copper to adhere to the furnace body without significantly reducing the heating efficiency of the object to be heated by the burner.

[0037] In the burner structure of the present invention, the distance from the innermost position on the other end side of the furnace frame introduction path to one end of the frame holder in the central axis direction of the burner is preferably 210 to 280 mm. By having the distance from the innermost position on the other end side of the furnace frame introduction path to one end of the frame holder in the above range in the central axis direction of the burner, it becomes easy to position the high-temperature part of the flame ejected from the burner near the innermost position on the other end side of the furnace frame introduction path or at a position overlapping the innermost position on the other end side of the furnace frame introduction path, so that the vicinity of the innermost position on the other end side of the furnace frame introduction path is efficiently heated, and the effect of preventing the resolidification of molten copper from adhering to the furnace body is enhanced without significantly reducing the heating efficiency of the heating target by the burner. On the other hand, if the distance from the innermost position on the other end of the furnace frame introduction path to one end of the frame holder in the central axis direction of the burner is less than the above range, the position of the opening of the frame holder is too close to the furnace interior, making it difficult for the high-temperature part of the flame ejected from the burner to heat the vicinity of the innermost position on the other end of the furnace frame introduction path, and if it exceeds the above range, the heating efficiency of the melting object by the flame ejected from the burner tends to decrease. Note that the distance from the innermost position on the other end of the furnace frame introduction path to one end of the frame holder in the central axis direction of the burner refers to the distance when viewed from the end surface overlapping the central axis of the burner.

[0038] In the burner structure of the present invention, the angle θ between the central axis of the burner and the straight line passing through the innermost position of the other end of the furnace frame introduction path and the innermost position of one end of the frame holder is preferably 5 to 8°. By making the angle θ between the central axis of the burner and the straight line passing through the innermost position of the other end of the furnace frame introduction path and the innermost position of one end of the frame holder within the above range, it becomes easy to position the high-temperature part of the flame ejected from the burner near the innermost position of the other end of the furnace frame introduction path or at a position overlapping the innermost position of the other end of the furnace frame introduction path, so that the vicinity of the innermost position of the other end of the furnace frame introduction path is efficiently heated, and the effect of preventing resolidification of molten copper from adhering to the furnace body is enhanced without significantly reducing the heating efficiency of the heating target by the burner. On the other hand, if the angle θ between the central axis of the burner and the straight line passing through the innermost position on the other end of the furnace frame introduction path and the innermost position on one end of the frame holder is less than the above range, the heating efficiency of the melting object by the flame ejected from the burner is likely to be low, and if it exceeds the above range, the position of the opening of the frame holder is too close to the furnace interior, making it difficult for the high-temperature part of the flame ejected from the burner to heat the vicinity of the innermost position on the other end of the furnace frame introduction path. Note that the angle θ between the straight line passing through the innermost position on the other end of the furnace frame introduction path and the innermost position on one end of the frame holder and the central axis of the burner refers to the angle θ when viewed from the end surface overlapping the central axis of the burner.

[0039] The combustion conditions of the fuel gas in the burner structure of the present invention, i.e., gas / air pressure, gas / air flow rate (combustion amount), air ratio, etc., are selected as normal conditions that do not cause flame lifting and efficiently burn the fuel gas. The burner structure of the present invention exerts an effect of making it difficult for re-solidified molten copper to adhere to the burner tile under combustion conditions that efficiently burn such normal combustion gas, without significantly decreasing the heating efficiency of the heating target by the burner.

[0040] In addition, when the burner structure of the present invention is installed in a copper shaft furnace, a preheating device for preheating the supporting combustible gas may not be provided, or a preheating device may be provided.

[0041] Hereinafter, the present invention will be described with reference to examples, but the present invention is not limited to the following examples.

Example

[0042] (Examples and Comparative Examples) The frame holder positions in the burner structure were set as shown in Table 1.

[0043]

Table 1

[0044] First, burner structures of each type were installed in the shaft furnace as follows, and copper melting was performed. · Arrangement of burner structures in the melting zone Of the six burner structures at the lowermost stage, two were No. 1 burner structures, and the remaining four were No. 2 burner structures. · Copper melting Implementation period: 1 week Burner combustion conditions: The control conditions of combustion (combustion amount, air ratio) are the same for No. 1 and No. 2.

[0045] After performing copper melting for one week and checking the adhesion status of the re-solidified product of the molten copper, in the No. 2 burner structure, which is a conventional burner structure, the adhesion of the re-solidified product of the molten copper occurred within several days, and removal work was required each time. In contrast, in the No. 1 burner structure of the present invention, there was no adhesion of the re-solidified product of the molten copper, and removal work was unnecessary.

[0046] Thereafter, the No. 1 burner structure was applied to all the burners at the lowermost stage of the shaft furnace, and copper melting was performed for six months. As a result, it was confirmed that there was no adhesion of the re-solidified product of the molten copper in any of the No. 1 burner structures. Furthermore, no deterioration in fuel consumption rate or adverse effects on material quality were observed, confirming that there were no problems. [Explanation of symbols]

[0047] 1, 30 Inside the copper shaft furnace 2, 32 Furnace body 3. 33 Burner 4, 34 Burner tile 5, 35 Frame holder 6 Innermost position on the other end of the furnace frame introduction path 7 Burner tile frame installation route 8, 38 Frame holder frame introduction route 9 Innermost position of one end of the frame holder 10a, 10b Burner structure of copper shaft furnace 11 Extension of the burner center line 12 A straight line passing through the innermost position of the other end of the furnace frame introduction path and the innermost position of one end of the frame holder 13 Furnace wall 14, 37 Furnace frame introduction path 39 Resolidified molten copper X is the distance from the innermost position on the other end of the furnace frame introduction path to one end of the flame holder in the direction of the central axis of the burner. θ is the angle between the central axis of the burner and a straight line passing through the innermost position of the other end of the furnace frame introduction path and the innermost position of one end of the frame holder.

Claims

1. A burner is installed outside the copper shaft furnace at a predetermined distance from the inner wall of the furnace so that an extension line of the central axis of the burner overlaps with the central axis of the furnace body frame introduction path formed in the furnace body of the furnace; A burner tile is installed in the furnace body of the furnace such that the opening on one end side faces one end side of the furnace body frame introduction path, the burner tile frame introduction path is formed to guide the flame emitted from the burner into the furnace, and the central axis of the burner tile frame introduction path overlaps with the extension line of the central axis of the burner; a flame holder having a flame holder frame introduction path formed therein, one end of which is inserted into the inside of the burner tile from the other end of the burner tile and opens into the burner tile frame introduction path, and the other end of which is connected to the burner and guides the flame emitted from the burner into the furnace, the flame holder being installed between the burner tile and the burner such that the central axis of the flame holder frame introduction path overlaps with an extension of the central axis of the burner; having The opening on one end side of the frame holder is positioned at a position where the high temperature part of the flame ejected from the burner can heat the vicinity of the innermost position on the other end side of the furnace body frame introduction path. A burner structure for a copper shaft furnace, comprising:

2. The burner structure of a copper shaft furnace according to claim 1, characterized in that the distance from the innermost position on the other end side of the furnace body frame introduction path to one end of the frame holder in the central axial direction of the burner is 210 to 280 mm.

3. The burner structure of a copper shaft furnace as described in claim 1, characterized in that the angle θ between a straight line passing through the innermost position of the other end side of the furnace body frame introduction path and the innermost position of one end of the frame holder and the central axis of the burner is 5 to 8 degrees.

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