JP2001116223A - Solid-gas mixing burner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solid-gas mixing burner which can enhance the reactivity between smelting material and reaction gas, by accelerating the premixing of smelting material flow and reaction gas flow. SOLUTION: This solid-gas mixing burner is equipped with a concentrate chute 11, a reaction gas feed pipe 12, a burner cone 13, a wind velocity adjuster 14, and an auxiliary burner 15 having a dispersing cone 16. The bottom 14a of the wind velocity adjuster 14 and the bottom 11a of the concentrate chute 11 are 20 mm ore more apart from each other so that the smelting material and the reaction gas may be premixed in the burner cone 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid-gas mixing burner, such as a concentrate burner, provided in a flash smelting furnace for feeding a smelting raw material and a reaction gas into the furnace.

[0002]

2. Description of the Related Art One of smelting furnaces using sulfide concentrate as a raw material is a flash smelting furnace called a flash smelting furnace. FIG. 6 is a schematic diagram showing an example of a basic configuration of a flash smelting furnace. The flash smelting furnace basically includes a reaction tower 2 provided with a concentrate burner 1 at the top, A settler 5 having one end connected to the lower part of the reaction tower 2 and provided with a lather port 3 and a cutout port 4 on the side surface, and a flue gas 6 connected to the other end of the settler 5. .

Conventionally, in such a flash smelting furnace, a powdery solid sulfide smelting raw material and a reaction gas such as oxygen-enriched air for reaction are used together with a concentrate burner provided at the top of a reaction tower 2. 1 is blown into the reaction tower 2. And reaction tower 2
In the inside, the solid sulfide smelting raw material blown in is heated by radiant heat in the furnace wall, heat of the auxiliary fuel or sensible heat of the reaction gas, instantaneously reacts with the reaction gas, and reacts with the settler 5.
Stored inside. In the settler 5, the melt is divided into Karami and Kawa according to the difference in specific gravity. Then, the lice are discharged from the lice extraction port 3 and introduced into the electric smelting furnace 7. On the other hand, the Kawa is extracted from the Kawa outlet 4 in response to a request in a batch process of a converter (not shown) which is the next step.

[0004] High-temperature exhaust gas generated in the reaction tower 2 is discharged through a settler 5 and a flue gas passage 6 and cooled by a boiler 8. The kalami that has entered the electric smelting furnace 7 is heated and held by the heat generated by the electric current supplied to the electrodes 9, and the kava suspended in the kalami further precipitates on the furnace bottom, leaving only the kalami containing a small amount of copper. Is discharged out of the furnace through the outlet 10. In this way, the solid sulfide smelting raw material is divided into Karami and Kawa.

A conventional ore burner provided in a flash smelting furnace as shown in FIG. 6 comprises a ore chute 11, a reaction gas feed pipe 12 and a reaction gas feed pipe 12 as shown in FIG. It has a burner cone 13 connected to the lower end of the pipe 12 and a fixed or movable wind speed regulator 14. The concentrate chute 11 is a tubular member for feeding a smelting raw material,
It extends vertically toward the reaction tower 2 (see FIG. 3).
The reaction gas feed pipe 12 is formed so that its diameter becomes smaller as it goes downward from a predetermined position in the pipe. The wind speed adjuster 14 is formed into a shape that narrows the flow width of the reaction gas formed by the reaction gas feed pipe 12 and the concentrate chute 11 to a predetermined size. It is provided on the outer periphery of 11 and is used to adjust the flow rate of the reaction gas to a predetermined speed. Concentrate chute 1
At the center of 1, an auxiliary burner 15 for raising the temperature of the reaction gas extends toward the reaction tower 2.

[0006] In the case of using a solid fuel such as fine ash as an auxiliary fuel, there is also a concentrate burner without the auxiliary burner as shown in the figure. At the tip of the auxiliary fuel burner 5, a concentrate chute 11 is provided.
A dispersing cone 16 is provided at a position where the smelting raw material sent vertically from the container collides. This dispersion cone 16
The smelting raw material is dispersed to facilitate contact with the reaction gas, and is used to prevent the generation of a so-called heap (lumps of unmelted material).

In such a concentrate burner, a solid sulfide smelting raw material is charged from a concentrate chute 11 on an outer periphery of an auxiliary fuel burner 15 and a reaction gas is further supplied to a reaction gas feed pipe on the outer periphery thereof. It is blown in from 12. After the solid sulfide smelting raw material exits from the concentrate chute 11, it comes into contact with the reaction gas adjusted to a predetermined flow rate via the wind speed adjuster 14, and the heat of the auxiliary fuel or the reaction gas is detected. The reaction proceeds by increasing the temperature by heat or radiant heat from the furnace inner wall.

[0008]

However, in the above-mentioned conventional concentrate burner, since the reaction gas adheres to the inner wall of the burner cone 13 and flows, it is difficult to flow toward the inside of the burner cone 13. For this reason, of the smelting raw materials discharged from the concentrate chute 11 into the burner cone 13, those flowing outside easily come into contact with the reaction gas, while those flowing inside have few chances to come into contact with the reaction gas. There was a problem that the reaction did not proceed easily. In particular, when the supply amount of the smelting raw material is increased, this tendency becomes conspicuous, and the position in the shaft at which the desired desulfurization rate is reached decreases, and the lower portion of the shaft burns rapidly in a limited range in the vertical direction. There is a problem that the heat load on the brick increases and the brick on the inner wall of the shaft becomes severely damaged. In addition, deterioration of separability of matte slag, increase in the rate of smoke ash generation, and the like also become problems. Finally, some of the concentrate dropped into the settler 5 without reacting, causing a problem that heap was generated.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and has as its object to reduce the flow of a smelting raw material stream through a reaction gas stream flowing along a burner cone inner wall. It is an object of the present invention to provide a solid-gas mixing burner such as a concentrate burner capable of promoting premixing of both by facilitating the flow in the direction and improving the reactivity between the smelting raw material and the reaction gas.

[0010]

To achieve the above object, a solid-gas mixing burner according to the present invention comprises a concentrate chute, a reaction gas feed pipe provided on the outer periphery of the concentrate chute, and a reaction gas feed pipe. The concentrate burner includes a burner cone connected to a lower end of a gas feed pipe, and a wind speed adjuster provided on an outer periphery of the concentrate chute to adjust a flow rate of a reaction gas flow to a predetermined speed. By setting the distance between the lower end of the ore chute and the lower end of the wind speed regulator to 20 mm or more, the reaction gas and the refining raw material are premixed in the burner cone.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on illustrated embodiments. FIG. 1 is a schematic configuration diagram of one embodiment of a solid-gas mixing burner according to the present invention, and FIG. 2 is an explanatory diagram showing a state of a smelting raw material flow in a burner cone of the solid-gas mixing burner shown in FIG. In the figure, members that are substantially the same as those in the above-described conventional example are given the same reference numerals, and descriptions thereof are omitted. Further, the solid-gas mixing burner of this embodiment is installed in a flash smelting furnace as shown in FIG.

As shown in FIG. 1, in the solid-gas mixing burner of this embodiment, the lower end 14a of the wind speed regulator 14 is at least 20 mm above the lower end 11a of the concentrate chute 11 (upstream of the reaction gas flow). ). The wind speed adjuster 14 is located at the lower end 14a in FIG.
12a or 14a in the conventional concentrate burner shown in
The cross-sectional area of the flow path formed by the wind speed regulator 14 and the reaction gas feed pipe 12 is designed so as to obtain the same predetermined flow velocity as that at the position. The burner cone 13
Is formed in a cylindrical shape, but may be formed in a truncated conical shape whose diameter increases as it goes downward, if necessary.

In the solid-gas mixing burner of this embodiment, a smelting raw material is charged from a concentrate chute 11 and a reaction gas is supplied from a reaction gas feed pipe 12 on the outer periphery thereof to a wind speed controller 1.
The flow rate is adjusted to a predetermined speed via 4 and sent in,
Both are supplied into the reaction tower of the flash smelting furnace. In this embodiment, since the lower end 14a of the wind speed adjuster 14 is arranged to be at least 20 mm above the lower end 11a of the concentrate chute 11, the vortex formed in the burner cone 13 as shown in FIG. Stabilizes. As a result, concentrate chute 1
Burner cone 1 near the outlet (lower end 14a)
3, the velocity component toward the inner wall becomes large, the smelting raw material stream flows toward the reaction gas stream, and premixing is efficiently performed.

Hereinafter, the function and effect of the present invention will be described in detail based on experimental results. In the above embodiment, the lower end 14a of the wind speed adjuster 14 is set at about 80 mm from the lower end 11a of the concentrate chute 11.
7 and the conventional ore burner (the lower end 14a of the wind speed adjuster 14 is positioned about 15 mm above the lower end of the ore chute 11) shown in FIG. The degree of premixing was compared. FIG. 3 shows the dependence of the pressure loss (blast pressure) on the charged amount of the smelting raw material in the solid-gas mixing burner according to the present embodiment and the concentrate burner of the conventional example.

In general, the pressure loss when the gas phase and the solid phase (the smelting raw material in the present invention) flow independently of each other does not depend on the charged amount. It is known that the pressure loss depends on the charge, since momentum exchange occurs between the solid phase and the gas phase. The pressure loss depending on the charging amount is called an additional pressure loss. Also,
It is known that in a steady state, the additional pressure loss is proportional to the solid phase charge (mass flow rate of particles).

FIG. 3 shows that when the lower end 14a of the wind speed regulator 14 is above the lower end 11a of the concentrate chute 11 and the separation distance is large, as in the solid-gas mixing burner of the embodiment of the present invention, The pressure loss depends on the smelting raw material charge,
Obviously, an additional pressure loss has occurred. Accordingly, it can be seen that premixing is performed in the solid-gas mixing burner of the embodiment of the present invention. On the other hand, like the conventional concentrate burner, the lower end 14a of the wind speed controller 14 and the concentrate chute 11
When the separation distance from the lower end 11a is small, it can be understood that the pressure loss hardly depends on the charged amount of the smelting raw material, and therefore, the premixing is not performed.

Next, the relationship between the above-mentioned separation distance and the blowing pressure (pressure loss) of the solid-gas mixing burner was examined while keeping other blowing conditions constant, and the results shown in FIG. 4 were obtained.
That is, when the separation distance is less than 20 mm, the blowing pressure shows a constant value without depending on the separation distance, but when the separation distance is 20 mm or more, the blowing pressure monotonously increases until the separation distance reaches 80 mm. From this, it is considered that premixing is not performed when the separation distance is less than 20 mm, and that when the separation distance is 20 mm or more, the amount of dry ore involved in premixing increases as the separation distance increases.

Further, in order to investigate a change in the performance of the solid-gas mixing burner due to the premixing, the dry ore during the falling of the shaft was water-cooled, and the desulfurization rate was analyzed. FIG. 5 shows the relationship between the desulfurization rate and the shaft vertical distance due to the difference in the separation distance. In the figure, the vertical axis of the shaft on the horizontal axis is standardized with 0 being the shaft ceiling and 1 being the melt level.
As is clear from this figure, there is no significant difference in the desulfurization rate arriving at the lower part of the shaft. It can be seen that the desulfurization performance has increased. Further, in the following table, the burner performance of the embodiment of the present invention (the distance: 80 mm) and the conventional example (the distance: 15 mm) are compared and shown. As is clear from this table, the smoke ash generation rate was about 5% when the separation distance was 15 mm, but was reduced to about 4% by increasing the separation distance to 80 mm. Also, oxygen efficiency was improved.

[0019]

As described above, according to the present invention, the amount of contact between the smelting raw material and the reaction gas is increased and the premixing is easily performed, and the reactivity between the smelting raw material and the reaction gas is significantly improved. Thus, a solid-gas mixture burner that can be improved can be provided. In particular, a solid-gas mixed burner that can obtain good oxygen efficiency and desulfurization performance and reduce smoke ash generation rate even if a large amount of smelting raw material is charged into the burner is compared with this type of conventional burner. Therefore, there is an advantage that it can be provided without increasing the manufacturing cost.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of one embodiment of a solid-gas mixing burner according to the present invention.

FIG. 2 is an explanatory diagram showing a state of a smelting raw material flow in a burner cone of the solid-gas mixing burner shown in FIG.

FIG. 3 is a graph showing the dependence of the pressure loss (blast pressure) on the charged amount of the smelting raw material in the embodiment of the present invention and the concentrate burner of the conventional example.

FIG. 4 is a diagram showing a relationship between a separation distance between a lower end of a wind speed adjuster and a lower end of a concentrate chute and a blowing pressure.

FIG. 5 is a diagram showing the relationship between the desulfurization rate and the shaft vertical distance in the embodiment of the present invention and the conventional example.

FIG. 6 is a schematic configuration diagram of a flash smelting furnace.

FIG. 7 is a schematic view of a conventional example of a concentrate burner.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Concentrate chute 11a Lower end of solid-gas mixing burner 12 Gas feed pipe for reaction 13 Burner cone 14 Wind speed regulator 14a Lower end of wind speed regulator 15 Auxiliary burner 16 Dispersion cone

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Keiji Fujita 17-5 Isoura-cho, Niihama-city, Ehime Prefecture Sumitomo Metal Mining Co., Ltd. Niihama Research Laboratory Co., Ltd. (72) Inventor Yasuhiro Kondo 17-5 Isoura-cho, Niihama-city, Ehime Prefecture Sumitomo Metal Niihama Research Laboratory, Mining Co., Ltd. (72) Inventor Yasuo Ojima 17-5 Isouracho, Niihama City, Ehime Prefecture F-term in Niihama Research Laboratories, Sumitomo Metal Mining Co., Ltd.

Claims (1)

[Claims] 1. A concentrate chute, a reaction gas feed pipe provided on an outer periphery of the concentrate chute, a burner cone connected to a lower end of the reaction gas feed pipe, and an outer periphery of the concentrate chute. In a solid-gas mixing burner provided with a wind speed adjuster for adjusting the flow rate of the reaction gas flow to a predetermined speed, the separation distance between the lower end of the concentrate chute and the lower end of the wind speed adjuster is set to 20 mm or more. A solid-gas mixing burner wherein the reaction gas and the refining raw material are premixed in the burner cone.