Concentrate burner, flash smelting furnace, and reaction gas introduction method

Abstract

This concentrate burner feeds a raw material into a flash furnace, and also feeds a reaction gas, which contributes to the reaction of the raw material, into at least the flash furnace. The concentrate burner comprises: a first cylindrical part provided outside a lance to form therebetween a raw material passage for feeding the raw material into the flash furnace; a second cylindrical part provided outside the first cylindrical part to form therebetween an annular first gas passage for feeding the reaction gas into the flash furnace; a third cylindrical part provided outside the second cylindrical part to form therebetween an annular second gas passage for feeding the reaction gas into the flash furnace; and a swirl vane projecting into the first gas passage and swirling the reaction gas passing through the first gas passage.　

Description

[Technical Field]

[0001] The present invention relates to a concentrate burner, a flash furnace and For reaction Regarding the gas introduction method. [Background technology]

[0002] A flash smelting furnace is a smelting furnace used for smelting non-ferrous metals such as copper and nickel, and for matte processing. It has a shaft installed above a reverberatory furnace-type settler, and gases for reaction with the raw materials are blown in from the top of the shaft to utilize the heat generated by oxidation to instantly oxidize and melt the raw materials. In a flash smelting furnace, the concentrate burner that supplies the raw materials and reaction gases into the furnace plays an important role in determining the performance of the flash smelting furnace. The performance of this concentrate burner determines the reaction efficiency and reaction rate of the raw materials in the reaction shaft, which in turn affects the processing capacity and metal recovery rate of the flash smelting furnace. It is desirable for the reaction in the reaction shaft of a flash smelting furnace to proceed quickly and uniformly with the same reaction rate for all raw materials. Therefore, it is desirable for the raw materials and reaction gases to be uniformly mixed.

[0003] In order to improve the mixing of the raw material and the reaction gas, a method is known in which the main airflow supplied from the concentrate burner into the reaction shaft is swirled (Patent Document 1). Also, it is known that an oxygen inlet pipe is provided inside the tubular concentrate chute surrounding the fuel burner, and a guide vane is provided at the opening of the pipe to supply a swirling flow (Patent Document 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Special Publication No. 2010-538162 [Patent Document 2] Japanese Patent Application Publication No. 60-248832 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the area directly below the concentrate burner where the raw materials are supplied is low in temperature due to the main airflow, making it difficult for the concentrate reaction to proceed. Patent Documents 1 and 2 do not actively generate a swirling flow in such an area directly below the raw material supply device, and there is room for improvement.

[0006] The present invention has been made in view of the above problems, and has as its object to actively promote the mixing of the raw materials and the reactive gas supplied into the flash smelting furnace, thereby making the reaction uniform. [Means for solving the problem]

[0007] The concentrate burner of the present invention is a concentrate burner that supplies raw materials into a flash smelting furnace and also supplies a reactive gas that contributes to a reaction of the raw materials into at least the flash smelting furnace, and includes: a first cylindrical portion that is provided outside a lance and forms a raw material flow path between itself and the lance for supplying the raw materials into the flash smelting furnace; a second cylindrical portion that is provided outside the first cylindrical portion and forms an annular first gas flow path between itself and the first cylindrical portion for supplying the reactive gas into the flash smelting furnace; a third cylindrical portion that is provided outside the second cylindrical portion and forms an annular second gas flow path between itself and the second cylindrical portion for supplying the reactive gas into the flash smelting furnace; and swirl blades that protrude into the first gas flow path and swirl the reactive gas passing through the first gas flow path. The time it takes for the reaction gas to pass between the upper end of the swirl vane and the upper edge of the second cylindrical portion is set to be between 0.5 ms and 3.7 ms.

[0008] The swirl vanes may be provided on the inner peripheral wall surface of the second cylindrical portion. The swirl vanes may be arranged with a gap between them and the first cylindrical portion. The inclination angle of the swirl vanes with respect to the axial direction of the lance may be in the range of 5° to 20°, and more preferably in the range of 10° to 15°.

[0009] Furthermore, the upper end of the swirl vane may be located below the upper edge of the second cylindrical portion, and a region for uniforming the flow rate of the gas introduced into the first gas flow passage may be provided between the upper end of the swirl vane and the upper edge of the second cylindrical portion. The distance between the upper end of the swirl vane and the upper edge of the second cylindrical portion is preferably 100 mm or more, more preferably 150 mm or more, and even more preferably 200 mm or more.

[0011] The flash smelting furnace of the present invention is equipped with the concentrate burner of the present invention.

[0012] Furthermore, the present invention For reactions The gas is introduced into the flash smelting furnace through a raw material flow path formed in the concentrate burner, together with the raw material introduced into the flash smelting furnace, at least through a first gas flow path formed around the raw material flow path and a second gas flow path formed around the first gas flow path. For reaction Introducing gas For reaction A method for introducing a gas, the gas being discharged through the first gas flow path For reactions The gas is introduced into the flash furnace as a swirling flow and discharged through the second gas flow path. For reaction The gas surrounds the swirling flow and flows into the flash furnace while suppressing the diffusion of the swirling flow. and a tubular portion that forms the first gas flow passage, and a swirl vane that generates the swirl flow is arranged in the tubular portion and is introduced into the tubular portion. For the above reaction The gas passage time is between 0.5 ms and 3.7 ms. This is how to introduce it. [Effects of the Invention]

[0013] In the present invention, the swirl blades provided at the lower end of the concentrate burner can promote mixing of the raw material and the reaction gas, making the reaction uniform. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a diagram showing a schematic configuration of a flash furnace for copper smelting according to an embodiment. [Figure 2] FIG. 2 is a cross-sectional view of a charging part provided at the tip of a concentrate burner provided in a flash smelting furnace according to an embodiment. [Figure 3] FIG. 3 is an enlarged cross-sectional view of the input portion shown in FIG. [Figure 4] FIG. 4 is a perspective explanatory view showing the arrangement of the swirl vanes. [Figure 5] FIG. 5 is an explanatory diagram of the attachment angle θ of the swirl vane and the flow velocity uniformity region. [Figure 6] FIG. 6 is a graph showing an example of a simulation result of the flow velocity distribution at the outlet of the first gas flow passage when no flow velocity uniforming region is provided. [Figure 7] FIG. 7 is a graph showing an example of the simulation results of the flow velocity distribution at the outlet of the first gas flow path when a flow velocity uniforming region with a vertical distance L1b=100 mm is provided. [Figure 8] FIG. 8 is a graph showing an example of the simulation results of the flow velocity distribution at the outlet of the first gas flow path when a flow velocity uniforming region with a vertical distance L1b of 200 mm is provided. [Figure 9] Figure 9(A) is an explanatory diagram showing the results of the reaction simulation when θ=0°, Figure 9(B) is the results of the reaction simulation when θ=10°, and Figure 9(C) is the results of the reaction simulation when θ=15°. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, a concentrate burner according to an embodiment will be described with reference to the drawings.

[0016] (Embodiment) As shown in FIG. 1, a flash smelting furnace 100 includes a concentrate burner 1 and a furnace body 2. The concentrate burner 1 is a raw material supply device that supplies the raw material concentrate (copper concentrate (e.g., CuFeS2)), a main reaction gas, an auxiliary reaction gas, and a dispersion gas (which also contributes to the reaction) into the furnace body 2. The furnace body 2 includes a reaction shaft 3 where the concentrate and the reaction gas are mixed, a settler 4, and an uptake 5. The main reaction gas and the auxiliary reaction gas are oxygen-enriched air, and the dispersion gas is air or oxygen-enriched air. These reaction gas and dispersion gas disperse and simultaneously oxidize the concentrate, separating it into matte and slag at the bottom of the reaction shaft 3.

[0017] Fig. 2 is an explanatory diagram showing the charging section 10 provided at the tip of the concentrate burner 1. Fig. 3 is an enlarged cross-sectional view of the charging section 10 shown in Fig. 2. The charging section 10 charges raw materials, reaction gas, and dispersion gas into the reaction shaft 3 side.

[0018] The input section 10 of the concentrate burner 1 includes a lance 11 provided at its center and a first cylindrical section 13 provided outside the lance 11 and forming a raw material flow path 12 between the lance 11 and the first cylindrical section 13. The input section 10 also includes a second cylindrical section 15a provided outside the first cylindrical section 13 and forming an annular first gas flow path 14 between the first cylindrical section 13 and the first cylindrical section 13 to supply the reaction gas into the flash smelting furnace 100 (reaction shaft 3). The input section 10 also includes a third cylindrical section 17a provided outside the second cylindrical section 15a and forming an annular second gas flow path 16 between the second cylindrical section 15a and the second cylindrical section 15a to supply the reaction gas into the flash smelting furnace 100 (reaction shaft 3). The input section 10 also includes a swirl vane 19 protruding into the first gas flow path 14 and swirling the reaction gas passing through the first gas flow path 14.

[0019] The lance 11 is disposed along a central axis AX extending in the vertical direction. The lance 11 includes a third gas passage 11a located at its center and a fourth gas passage 11b arranged around the third gas passage 11a. A reaction auxiliary gas, which is part of the reaction gas, passes through the third gas passage 11a. A dispersion gas passes through the fourth gas passage 11b. A hollow truncated conical dispersion cone 111 is disposed at the tip (lower end) of the lance 11. A plurality of supply holes 111a are formed on the lower side of the dispersion cone 111 to discharge the dispersion gas that has passed through the fourth gas passage 11b into the reaction shaft 3. In this embodiment, the supply holes 111a are disposed so that the gas discharge direction is normal to the base circle of the dispersion cone 111. However, the supply holes 111a may be disposed so that the gas discharge direction is angled with respect to the normal to the base circle of the dispersion cone 111.

[0020] The first cylindrical portion 13 is formed by a cylindrical member arranged so as to surround the lance 11. The first cylindrical portion 13 in this embodiment is provided as a water-cooled nozzle in which cooling water circulates.

[0021] A raw material flow path 12 formed between the lance 11 and the first cylindrical portion 13 supplies the concentrate into the reaction shaft 3 .

[0022] The second cylindrical portion 15a is provided as part of the inner tank member 15 arranged outside the first cylindrical portion 13. The inner tank member 15 has a funnel-shaped portion 15b at its upper portion, which expands in diameter toward the top, and a cylindrical second cylindrical portion 15a connected to the bottom of the funnel-shaped portion 15b. The funnel-shaped portion 15b forms a first air chamber 151 between itself and the first cylindrical portion 13. The first air chamber 151 is connected to the first gas flow path 14. The inner tank member 15 is provided in a detachable manner.

[0023] The third cylindrical portion 17a is provided as the inner peripheral wall portion of the cooling jacket 17 provided at the lower end of the charging portion 10. Cooling water circulates inside the cooling jacket 17. The cooling jacket 17 is disposed above it and connected to a funnel-shaped outer tank member 18 that expands in diameter toward the top. Specifically, the cooling jacket 17 is attached to a flange-shaped portion 18a provided at the lower end of the outer tank member 18. A second air chamber 181 is formed between the outer tank member 18 and the inner tank member 15. The second air chamber 181 is connected to the second gas flow path 16.

[0024] The concentrate burner 1 has a first gas supply system 21 and a second gas supply system 22. The first gas supply system 21 is branched into a first supply section 21a and a second supply section 21b. The first supply section 21a supplies gas into the first air chamber 151. On the other hand, the second supply section 21b supplies gas into the second air chamber 181. The first supply section 21a is provided with an adjustment valve 21a1 that adjusts the gas flow rate, which makes it possible to adjust the ratio between the amount of gas supplied into the first air chamber 151 and the amount of gas supplied into the second air chamber 181. The second gas supply system 22 supplies gas into the lance 11. The total amount of gas supplied by the first gas supply system 21 and the total amount of gas supplied by the second gas supply system 22 can also be adjusted.

[0025] In this embodiment, the first supply unit 21a further branches into two paths. The first air chamber 151 has gas inlets 151a at two locations in its upper part, and each of the paths branching from the first supply unit 21a is connected to one of the gas inlets. The first air chamber 151 has a larger upper dimension than a lower dimension. When blowing gas into the first air chamber 151 having such a larger upper dimension, it is desirable to provide gas inlets at multiple locations so that the gas is distributed throughout the entire first air chamber 151. Furthermore, it is desirable that the multiple gas inlets be provided radially from the center of the first air chamber 151 or symmetrically about the central axis AX. Therefore, in this embodiment, the gas inlets 151a are provided at two locations symmetrically about the central axis AX.

[0026] Swirl vanes 19 are provided in the first gas flow path 14. The swirl vanes 19 are provided on the inner circumferential wall surface 15a1 of the second cylindrical portion 15a so as to protrude into the first gas flow path 14. By providing the swirl vanes 19 on the inner circumferential wall surface 15a1 of the second cylindrical portion 15a included in the removable inner tank member 15, cleaning and maintenance work around the swirl vanes 19 becomes easier. The swirl vanes 19 also function as spacers between the first cylindrical portion 13 and the second cylindrical portion 15a. That is, the swirl vanes 19 also have the function of maintaining the distance between the first cylindrical portion 13 and the second cylindrical portion 15a.

[0027] 3, the swirl vane 19 is disposed with a gap S1 between it and the first cylindrical portion 13. The gap S1 is provided in this manner to accommodate dimensional changes that occur due to thermal expansion of the components.

[0028] 4 and 5, the arrangement of the swirl vanes 19 will be described in more detail. The distance that the second cylindrical portion 15a extends in the vertical direction is L1. The swirl vanes 19 are provided in the second cylindrical portion 15a, but the upper ends 19a of the swirl vanes 19 are located below the upper edge 15a3 of the second cylindrical portion 15a. The vertical length of the swirl vanes 19 is L1a. As a result, a region 30 (hereinafter referred to as the "flow velocity uniforming region") that uniforms the flow velocity of the gas introduced into the first gas flow passage 14 is provided between the upper ends 19a of the swirl vanes 19 and the upper edge 15a3 of the second cylindrical portion 15a. In other words, the flow velocity uniforming region 30 is provided at the transition position from the funnel-shaped portion 15b to the second cylindrical portion 15a. The flow velocity uniform region 30 is a region indicated by hatching in FIG. 5, in which the inner peripheral wall surface 15a1 of the second cylindrical portion 15a is exposed over the entire periphery.

[0029] The vertical distance of the flow velocity uniformization region 30 is L1b. The lower end 19b of the swirl vane 19 coincides with the lower edge 15a4 of the second cylindrical portion 15a. The lower end 19b of the swirl vane 19 does not necessarily have to coincide with the lower edge 15a4, but by aligning it with the lower edge 15a4, it is advantageous in that the gas can be discharged without attenuating the momentum of the swirling flow generated by the swirl vane 19.

[0030] The lower edge 15a4 of the second cylindrical portion 15a serves as the outlet of the first gas flow path 14. From the viewpoint of promoting mixing of the raw materials and the reaction gas and making the reaction uniform, it is desirable that the flow rate of the gas at the outlet of the first gas flow path 14 be uniform over the entire circumference of the first gas flow path 14. However, in this embodiment, gas is blown into the first air chamber 151 from two gas blowing ports 151a. This may cause variations in the flow rate of the gas flowing from the funnel-shaped portion 15b into the first cylindrical portion 15a.

[0031] Therefore, in this embodiment, a flow velocity uniforming region 30 is provided between the upper end portion 19a of the swirl vane 19 and the upper edge 15a3 of the second cylindrical portion 15a. Here, the effect of providing the flow velocity uniforming region 30 will be described with reference to Figs. 6 to 8.

[0032] In the flash smelting furnace 100 of this embodiment, the flow velocity of the gas introduced into the second cylindrical portion 15a during operation is assumed to be approximately 110 m / s to 130 m / s. Therefore, the simulation was performed under the condition that the average flow velocity of the gas flowing into the flow velocity uniformization region 30 is 120 m / s. The simulation was performed using scFLOW from Software Cradle Co., Ltd. As an example, the number of swirl vanes was set to 12, evenly spaced in the circumferential direction. The horizontal width of the swirl vane was set to 90% of the width of the gas flow path 14. The length L1 was set to 500 mm or more and between 0.5 and 2 times the outer diameter of the second cylindrical portion 15a. The angle of the swirl vane 19 was set to 10°, as an example. The average flow velocity here refers to the average value of the flow velocity around the entire circumference of the upper edge 15a3 of the second cylindrical portion 15a. The flow velocity of the gas introduced into the second cylindrical portion 15a at an average velocity of 120 m / s is increased in the region where the swirl vanes 19 are provided. This is thought to be because the gas flow passage area in the region where the swirl vanes 19 are provided is reduced by the volume of the swirl vanes 19, thereby increasing the flow velocity of the gas passing between the swirl vanes 19. In this embodiment, the average flow velocity at the outlet of the first gas flow passage 14 is 124.2 m / s. This average flow velocity refers to the average value of the flow velocity around the entire circumference of the lower edge 15a4 of the second cylindrical portion 15a. During actual operation of the flash smelting furnace 100, the flow velocity of the gas introduced into the second cylindrical portion 15a can be adjusted by adjusting the aperture of the regulating valve 21a1.

[0033] FIG. 6 shows a simulation result of a comparative example, specifically, an example of the simulation result of the flow velocity distribution at the outlet of the first gas flow passage 14 when no flow velocity uniformization region is provided. In this simulation, the mounting angle θ of the swirl vanes 19 is set to 10°. This also applies to the following simulations. The mounting angle θ is the inclination angle of the swirl vanes 19 with respect to the central axis AX extending in the vertical direction (the mounting angle θ will be described in detail later). Here, the case where no flow velocity uniformization region is provided refers to the case where the swirl vanes 19 are provided over the entire vertical area of ​​the second cylindrical portion 15a. In this case, the variation in the flow velocity at the outlet of the first gas flow passage 14 is approximately ±2.0% with respect to the average flow velocity of 124.2 m / s.

[0034] Specifically, at the point where the flow velocity at the outlet of the first gas flow path 14 was the slowest, the difference from the average flow velocity of 124.2 m / sec was -2.6%, and at the point where the flow velocity at the outlet of the first gas flow path 14 was the fastest, the difference from the average flow velocity of 124.2 m / sec was +2.0%. Note that a "- (minus)" indicates a slower flow velocity than the average flow velocity, and a "+ (plus)" indicates a faster flow velocity than the average flow velocity. This also applies to the following explanation.

[0035] Next, referring to FIG. 7, when the vertical distance L1b of the flow velocity uniform region 30 is 100 mm, the variation in flow velocity at the outlet of the first gas flow passage 14 is approximately ±1.5% with respect to the average flow velocity of 124.2 m / sec.

[0036] Specifically, at the location where the flow velocity at the outlet of the first gas flow path 14 was the slowest, the difference from the average flow velocity of 124.2 m / sec was −1.8%, and at the location where the flow velocity at the outlet of the first gas flow path 14 was the fastest, the difference from the average flow velocity of 124.2 m / sec was +1.4%. Thus, by providing the flow velocity uniform region 30, the variation in the flow velocity at the outlet of the first gas flow path 14 was improved.

[0037] Next, referring to FIG. 8, when the vertical distance L1b of the flow velocity uniform region 30 is 200 mm, the variation in flow velocity at the outlet of the first gas flow passage 14 is approximately ±1% of the average flow velocity of 124.2 m / sec.

[0038] Specifically, at the location where the flow velocity at the outlet of the first gas flow path 14 was slowest, the difference from the average flow velocity of 124.2 m / s was −1.0%, and at the location where the flow velocity at the outlet of the first gas flow path 14 was fastest, the difference from the average flow velocity of 124.2 m / s was +0.9%. That is, by increasing the vertical distance L1b of the flow velocity uniformization region 30, further improvement in the variation in the flow velocity at the outlet of the first gas flow path 14 was observed. As described above, by increasing the vertical distance L1b, the variation in the flow velocity at the outlet of the first gas flow path 14 can be improved. For this reason, although simulation results are not shown, the vertical distance L1b of the flow velocity uniformization region 30 may be set to 150 mm, for example, to improve the variation in the flow velocity at the outlet of the first gas flow path 14.

[0039] 7 and 8, it is believed that the longer the vertical distance L1b of the flow velocity uniforming region 30, the greater the effect of uniforming the flow velocity. However, when no swirl vanes 19 are provided on the inner peripheral wall surface of the second cylindrical portion 15a, the flow velocity at the outlet of the first gas flow passage 14 varies by approximately ±1% of the average flow velocity. Therefore, the upper limit of the effect of the flow velocity uniforming region 30 is approximately ±1% of the average flow velocity, and it is believed that if the vertical distance L1b = 200 mm that achieves this, it will be possible to obtain approximately the same effect as when no swirl vanes 19 are provided.

[0040] Here, the vertical distance L1b of the flow velocity uniforming region 30 is designed according to the scale of the flash smelting furnace 100 and the dimensions of the concentrate burner 1, and the dimensions may be changed as appropriate. Therefore, the vertical distance L1b of the flow velocity uniforming region 30 should be at least 100 mm or more, and the upper limit is not particularly determined, but can be set to 400 mm or less depending on various conditions of the flash smelting furnace 100 and the concentrate burner 1.

[0041] However, in this case, the vertical length L1a of the swirl vane 19 must be long enough to generate the desired swirling flow, and the vertical distance L1b of the flow velocity uniforming region 30 is set within a range that satisfies this condition. For example, if the vertical distance L1 of the second cylindrical portion 15a is 700 mm and the vertical distance L1b of the flow velocity uniforming region 30 is set to 100 mm, the vertical length L1a of the swirl vane 19 will be 600 mm. Similarly, if the vertical distance L1b of the flow velocity uniforming region 30 is set to 400 mm, the vertical length L1a of the swirl vane 19 will be 300 mm. In this case, if an appropriate swirling flow is generated, the vertical distance L1b of the flow velocity uniforming region 30 may be set to 400 mm.

[0042] In the above simulation, the average flow velocity of the gas flowing into the flow velocity uniformity region 30 was 120 m / s (the average flow velocity at the outlet of the first gas flow path 14 was 124.2 m / s), but similar trends were observed in other flow velocity ranges.

[0043] For example, when the average flow velocity of the gas flowing into the flow velocity uniform region 30 during operation is 110 m / sec, the average flow velocity at the outlet of the first gas flow passage 14 is 113.8 m / sec. Under these flow velocity conditions, a simulation was performed with the vertical distance L1b of the flow velocity uniform region 30 set to 200 mm, and the following results were obtained: At the location where the flow velocity at the outlet of the first gas flow passage 14 was the slowest, the difference from the average flow velocity of 113.8 m / sec was −1.0%, and at the location where the flow velocity at the outlet of the first gas flow passage 14 was the fastest, the difference from the average flow velocity of 113.8 m / sec was +1.2%.

[0044] Furthermore, when the average flow velocity of the gas flowing into the flow velocity uniform region 30 during operation is 130 m / sec, the average flow velocity at the outlet of the first gas flow passage 14 is 134.5 m / sec. Under these flow velocity conditions, a simulation was performed with the vertical distance L1b of the flow velocity uniform region 30 set to 200 mm, and the following results were obtained: At the location where the flow velocity at the outlet of the first gas flow passage 14 was the slowest, the difference from the average flow velocity of 134.5 m / sec was −0.8%, and at the location where the flow velocity at the outlet of the first gas flow passage 14 was the fastest, the difference from the average flow velocity of 134.5 m / sec was +1.1%.

[0045] Here, since the flow velocity of the gas is considered to be uniformed by passing through an area of ​​the second cylindrical portion 15a where the swirl vanes 19 are not provided, it is considered necessary for the gas to pass through such an area for a predetermined time. Specifically, the time required for the gas to pass between the upper end 19a of the swirl vane 19 and the upper edge 15a3 of the second cylindrical portion 15a, i.e., the time required for the gas to pass through the flow velocity uniformity area 30, can be set to between 0.5 ms and 3.7 ms.

[0046] For example, when the vertical distance L1b of the flow velocity uniforming region 30 is 100 mm (=0.1 m), the average flow velocity of the gas in the flow velocity uniforming region 30 is 130 m / sec, which is the fastest flow velocity expected in an operating state. Under this condition, it takes 0.1 (m) ÷ 130 (m / sec) = 0.77 ms for the gas to pass through the flow velocity uniforming region 30.

[0047] Furthermore, when the vertical distance L1b of the flow velocity uniforming region 30 is 400 mm (=0.4 m), the average flow velocity of the gas in the flow velocity uniforming region 30 is 110 m / sec, the slowest flow velocity expected in an operating state. Under this condition, it takes 0.4 (m) ÷ 110 (m / sec) = 3.63 ms for the gas to pass through the flow velocity uniforming region 30.

[0048] In this way, the vertical distance L1 of the flow velocity uniforming region 30 may be determined by the time it takes to pass through the flow velocity uniforming region 30.

[0049] In this way, the range of the flow velocity uniformity region 30 can be set based on at least either the distance or the flow velocity.

[0050] By making the outlet flow velocity of the first gas flow channel 14 uniform over the entire circumference, it is possible to further promote the mixing of the raw materials and the reaction gas and make the reaction uniform. This is particularly effective when blowing gas into the air chamber 151 from one or two locations, because the flow velocity of the gas flowing from the funnel-shaped portion 15b into the second cylindrical portion 15a is likely to vary.

[0051] Next, the mounting angle θ of the swirl vane 19 will be described with reference to Figures 4 and 5 again, as well as Figure 9. The mounting angle θ of the swirl vane 19 is the angle of inclination relative to the axial direction of the lance 11, i.e., the central axis AX extending in the vertical direction. In Figure 5, the axis AX1 indicates an axis parallel to the central axis AX, and when the longitudinal direction of the swirl vane 19 coincides with the direction along the axis AX1, the mounting angle θ is expressed as 0°.

[0052] Such an attachment angle θ can be set in the range of 5° to 20°, and is preferably set in the range of 10° to 15°.

[0053] Figures 9(A) to 9(C) show the results of reaction simulations in the reaction shaft 3 for different mounting angles θ of the swirl vanes 19. Figure 9(A) shows the results of the reaction simulation when θ = 0°, Figure 9(B) shows the results of the reaction simulation when θ = 10°, and Figure 9(C) shows the results of the reaction simulation when θ = 15°.

[0054] 9(A) to 9(C), the reference symbol AR indicates the reaction region in the furnace. The lowest point of the reaction region AR can be used as an index for evaluating the state of the reaction in the furnace as the reaction point height. That is, when the reaction point height is high, the raw material and the reaction gas are actively mixed in the region near the inlet 10, and it can be evaluated that the reaction state in the furnace is good.

[0055] FIG. 9(A) shows the case where θ=0°. If the reaction site height at this time is h0, then the reaction site height h1 at θ=10° shown in FIG. 9(B) is higher than the reaction site height h0. Furthermore, the reaction site height h2 at θ=15° shown in FIG. 9(C) is higher than the reaction site height h1. As can be seen, the reaction site height increases as the mounting angle θ increases. In other words, as the mounting angle θ increases, the diffusion of the raw material is promoted, and the mixing of the raw material and the reactive gas is actively carried out. Since the diffusion of the raw material is promoted as the mounting angle θ increases, even when the mounting angle θ is increased beyond 0°, for example, at θ=5°, the diffusion of the raw material and the mixing of the raw material and the reactive gas can be promoted. Furthermore, the mounting angle θ may be increased beyond θ=15°, for example, to θ=20°, to promote the diffusion of the raw material and the mixing of the raw material and the reactive gas.

[0056] As described above, it has been found that the diffusion of the raw material is promoted as the mounting angle θ of the swirl vane 19 is increased, but there is a concern that if the mounting angle θ of the swirl vane 19 is increased, the particles contained in the raw material will be more likely to head toward the wall surface of the flash smelting furnace 100, increasing the possibility of collision with the furnace wall. However, the concentrate burner 1 of this embodiment is equipped with the first gas passage 14 and the second gas passage 16 located outside it, and the gas passing through the first gas passage 14 For reaction Only the gas is made to swirl. For reaction The gas is swirling but passes through the second gas flow path 16 For reaction The gas is discharged downward from the flash furnace 100. Moreover, the gas passes through the second gas passage 16. For reaction The gas is in a swirling flow For reaction Therefore, the gas discharged from the first gas flow passage 14 becomes a swirling flow. For reaction The gas is discharged through the second gas flow path 16. For reactions The gas suppresses the diffusion of the particles in the raw material, making it difficult for the particles to move toward the wall of the flash furnace 100.

[0057] In addition, this phenomenon of particles in the raw materials moving toward the wall surface of the flash smelting furnace 100 can be suppressed by adjusting the amount of dispersion gas supplied from the fourth gas flow path 11b through the supply holes 111a provided in the dispersion cone 111.

[0058] The likelihood of particles colliding with the wall surface (furnace wall) inside the furnace can be evaluated by the wall collision particle ratio. The wall collision particle ratio is the ratio of the amount of particles that collide with the furnace wall and are trapped to the amount of raw material charged into the furnace. The furnace wall is mainly the wall surface of the reaction shaft 3.

[0059] Here, an example of a simulation result in which the wall-impingement particle ratio was calculated is shown. The simulation was performed using FLUENT, a general-purpose thermal fluid software by ANSYS. In the simulation, the copper concentrate charging rate (t / h) was the same for all the channels, and the total airflow rate (dispersion gas volume) of the first gas flow path 14, the second gas flow path 16, the third gas flow path 11a, and the fourth gas flow path 11b (hereinafter referred to as the total airflow rate) was constant. The sum of the airflow rates of the first gas flow path 14 and the second gas flow path 16 was set to be 90% or more of the total airflow rate, and the ratio of the airflow rate of the first gas flow path 14 to the airflow rate of the second gas flow path 16 was set to approximately 1:1. When the amount of dispersion gas was varied, the amount of airflow of the second gas flow path 16 was increased to compensate for the decrease in the amount of dispersion gas, thereby maintaining the total airflow rate constant. Below, the wall collision particle ratios are shown for the installation angles θ of the swirl vane 19 = 0°, 10°, and 15°. The amount of dispersion gas is uniformly 40 Nm 3 / min. As a result, for example, the wall collision particle ratio was 10.9% when the mounting angle θ of the swirl vanes 19 was 0°, and the wall collision particle ratio was 11.6% when the mounting angle θ of the swirl vanes 19 was 10°. Furthermore, the wall collision particle ratio was 14.6% when the mounting angle θ of the swirl vanes 19 was 15°. Thus, the simulation showed that the wall collision particle ratio increases as the mounting angle θ of the swirl vanes 19 increases. The wall collision particle ratio is an average value of multiple simulation results.

[0060] Next, the simulation results are shown in which the amount of dispersion gas is reduced as the mounting angle θ of the swirl vane 19 increases. When the mounting angle θ of the swirl vane 19 is 10°, the amount of dispersion gas is reduced to 40 Nm 3 / min less than 38.5Nm 3 / min, the wall collision particle ratio could be reduced to 11.2%. Furthermore, when the installation angle θ of the swirl vane 19 was set to 40 Nm 3 / min less than 35Nm 3 By setting the installation angle θ at θ = 20°, which is larger than θ = 15°, the wall-impingement particle ratio was reduced to 11.4%. Thus, adjusting the amount of dispersion gas can be expected to improve the wall-impingement particle ratio. For example, even when the installation angle θ is set to θ = 20°, which is larger than θ = 15°, adjusting the amount of dispersion gas accordingly can suppress the increase in the wall-impingement particle ratio while promoting the dispersion of the raw material and the mixing of the raw material with the reaction gas. However, when θ exceeds θ = 20°, a significant reduction in the amount of dispersion gas is required to suppress the increase in the wall-impingement particle ratio. This tends to negate the effect of the inner cylinder air swirl on increasing the reaction sites. Therefore, it is desirable to set the installation angle of the swirl impeller to an upper limit of 20°. A similar trend was observed in simulations in which the amount of raw material charged into the furnace was changed.

[0061] This allows the proportion of particles colliding with the wall to be maintained at the same level regardless of the mounting angle θ of the swirl vane 19. The amount of the reduced dispersion gas is compensated for by the amount of the particles passing through the second gas passage 16. For reactions By increasing the amount of gas For reactions The total amount of gas is added together.

[0062] In this way, by adjusting the amount of dispersion gas, it is possible to obtain the effect of increasing the reaction point height while maintaining the proportion of particles that collide with the wall.

[0063] According to the concentrate burner 1 of this embodiment, the gas passing through the first gas passage 14 For reactionSince the gas is swirled, the mixing of the raw material and the reaction gas is actively promoted, and the reaction can be made uniform. In the flash smelting furnace 100, the total amount of blown air may be adjusted depending on the amount of charge into the furnace. For example, when the amount of charge decreases, the total amount of blown air is reduced from the viewpoint of heat balance. In this case, the gas passing through the first gas flow path 14 is basically For reactions The amount of gas is kept constant and passes through the second gas flow path 16. For reaction The amount of gas is reduced. However, the amount of gas passing through the second gas flow path 16 is For reaction If the amount of gas is reduced too much, the adhesion of the molded article to the periphery of the third cylindrical portion 17a becomes easy to occur, and the disturbance of the air flow becomes easy to occur. For reactions A lower limit may be set for the amount of gas. Therefore, depending on the amount of gas charged and the quality of the raw material, the amount of gas passing through the second gas flow path 16 may be increased. For reactions The amount of gas passes through the first gas flow path 14 so as not to fall below the lower limit. For reactions The amount of gas passing through the first gas flow path 14 may be reduced. For reactions When the amount of gas is reduced, the gas passes through the first gas flow path 14. For reactions Therefore, as in the concentrate burner 1 of this embodiment, by providing a protruding swirl blade 19 in the first gas passage 14, it is possible to actively promote the mixing of the raw material and the reaction gas.

[0064] The above-described embodiment is a preferred example of the present invention, but the present invention is not limited to this and can be modified in various ways without departing from the spirit of the present invention. [Explanation of symbols]

[0065] 1 concentrate burner 2 Furnace body 3 Reaction Shaft 4 Setra 5 Uptake 11. Lance 12 Raw material flow path 13 First cylindrical portion 14 First gas flow path 15 Inner tank components 15a second cylindrical portion 16 Second gas flow path 17 Cooling jacket 18 Outer tank component 19 Swirl blades

Claims

1. A concentrate burner that supplies raw materials into a flash smelting furnace and also supplies a reaction gas that contributes to a reaction of the raw materials into at least the flash smelting furnace, a first cylindrical portion provided outside the lance and forming a raw material flow path between the lance and the first cylindrical portion for supplying the raw material into the flash smelting furnace; a second cylindrical portion provided outside the first cylindrical portion and forming, between the first cylindrical portion and the second cylindrical portion, a first annular gas flow path for supplying the reaction gas into the flash smelting furnace; a third cylindrical portion provided outside the second cylindrical portion and forming, between the third cylindrical portion and the second cylindrical portion, an annular second gas flow path for supplying the reaction gas into the flash smelting furnace; a swirl vane that protrudes into the first gas flow path and swirls the reactant gas passing through the first gas flow path; a funnel-shaped portion having an inclined surface that expands in diameter upward, the upper edge of the second cylindrical portion being connected to a lower end of the inclined surface; a flow velocity uniforming region formed between an upper end of the swirl vane and the upper edge of the second cylindrical portion, for uniforming the flow velocity of the reactant gas introduced into the first gas flow path; The dimension of the flow velocity uniforming region along the axial direction of the second cylindrical portion is 100 mm or more and 400 mm or less, and the time it takes for the reaction gas passing through the first gas flow path to pass through the flow velocity uniforming region is between 0.5 ms and 3.7 ms. Concentrate burner.

2. The concentrate burner according to claim 1 , wherein the swirl vanes are provided on an inner peripheral wall surface of the second cylindrical portion.

3. The concentrate burner according to claim 2 , wherein the swirl vane is disposed with a gap between it and the first cylindrical portion.

4. 4. The concentrate burner according to claim 1, wherein the angle of inclination of the swirl vanes relative to the axial direction of the lance is in the range of 5° to 20°.

5. 5. The concentrate burner according to claim 4, wherein the angle of inclination of said swirl vanes relative to the axial direction of said lance is in the range of 10 to 15 degrees.

6. 2. The concentrate burner according to claim 1, wherein the distance along the axial direction of the second cylindrical portion between the upper end of the swirl vane and the upper edge of the second cylindrical portion is 100 mm or more.

7. 7. The concentrate burner according to claim 6, wherein the distance between the upper end of the swirl vane and the upper edge of the second cylindrical portion along the axial direction of the second cylindrical portion is 150 mm or more.

8. 8. The concentrate burner according to claim 7, wherein the distance along the axial direction of the second cylindrical portion between the upper end of the swirl vane and the upper edge of the second cylindrical portion is 200 mm or more.

9. A flash smelting furnace equipped with a concentrate burner described in any one of claims 1 to 8.

10. A method for introducing a reactive gas into a flash smelting furnace through at least a first gas flow path formed around a raw material flow path formed in a concentrate burner and a second gas flow path formed around the first gas flow path, together with raw materials charged into the flash smelting furnace through the raw material flow path formed in the concentrate burner, comprising: the reactive gas discharged through the first gas flow passage is introduced into the flash smelting furnace as a swirling flow, and the reactive gas discharged through the second gas flow passage is introduced into the flash smelting furnace while surrounding the swirling flow and suppressing diffusion of the swirling flow, a funnel-shaped section having an inclined surface whose diameter increases upward, the funnel-shaped section having an upper edge connected to a lower end of the inclined surface, the funnel-shaped section being disposed within a cylindrical section forming the first gas flow path, the funnel-shaped section having an inclined surface whose diameter increases upward, the funnel-shaped section having an upper edge connected to a lower end of the inclined surface, the funnel-shaped section being disposed within the first gas flow path ... being disposed within the first gas flow path, the funnel-shaped section having an inclined surface

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