JP2004244666A - Converter operation method in smelting metal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a converter operation method for improving the productivity of crude copper by increasing a quantity of white matte in a step of manufacturing copper through increasing the quantity of the molten matte to be charged into a converter, and by preventing a blowing-up phenomenon of the white matte owing to blowing of an oxygen-containing gas. <P>SOLUTION: The converter operation method for manufacturing crude copper through accommodating the molten matte in the converter 1 and blowing the oxygen-containing gas, comprises oxidizing the molten matte in the converter by blowing the oxygen-containing gas to separate it into the white matte and slag, removing the slag, further discharging 20 to 30 mass% of the white matte from the converter, blowing the oxygen-containing gas into the white matte in the converter for 30 to 120 minutes, then returning the white matte once discharged from the converter into the converter, and blowing the oxygen-containing gas. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method of operating a converter for producing a coarse metal from a molten mat in a smelting process of a non-ferrous metal.
[0002]
[Prior art]
Generally, in the smelting and refining of non-ferrous metals (eg, copper, nickel, etc.), the dried concentrate is smelted in a flash smelting furnace and separated into a molten mat (hereinafter referred to as a smelting mat) and slag. The molten mat obtained in the furnace is charged into a converter, and an oxygen-containing gas (for example, the atmosphere, oxygen-enriched air, etc.) is blown to cause an oxidation reaction (hereinafter referred to as oxygen-containing gas blowing). The quality of the molten mat is enhanced to produce crude metal (for example, crude copper, crude nickel, etc.).
[0003]
Hereinafter, the case of copper smelting will be described.
In blowing oxygen-containing gas from a molten mat using a converter, the converter is first tilted and the molten mat is charged into the converter. Next, after erecting the converter, an oxygen-containing gas is blown from the tuyere. In this way, the impurity components in the molten mat are oxidized and separated, thereby improving the quality of the molten mat.
[0004]
That is, the copper content in the molten mat obtained in the flash smelting furnace is about 50 to 65% by mass, but by blowing oxygen-containing gas in the converter, the impurity components in the molten mat are converted into oxides to form slag. Or SO ₂ gas to enhance the quality of the molten mat. As a result, blister copper having a copper content of about 97 to 99% by mass is obtained.
Oxygen-containing gas blowing in a converter is roughly divided into a period in which slag is generated (so-called copper making period) and a period in which molten white glue (that is, Cu ₂ S phase) is oxidized into blister copper (so-called copper making period). Is done.
[0005]
The fermentation period may be divided into, for example, a first fermentation period and a second fermentation period. In each case, FeS in the molten mat is oxidized by oxygen-containing gas blowing to separate into slag, and whitening is performed. This is a period during which a reaction for generating a Cu ₂ S phase called glue proceeds.
The copper making period is a period in which, after removing the slag generated in the fermentation period, the white glue (that is, the Cu ₂ S phase) is further oxidized by oxygen-containing gas blowing to advance a reaction for producing blister copper. Immediately after the start of the oxygen-containing gas blowing in the copper-making period, the oxidation reaction is not stable, and the flow rate of the oxygen-containing gas blown into the white mold (that is, the blowing amount) fluctuates.
[0006]
When blowing oxygen-containing gas by increasing the amount of molten mat to be charged into the converter to improve the productivity of blister copper, remove the slag generated during the fermentation period, and then The amount of white glue housed inside also increases and the bath surface rises. For this reason, the hydrostatic pressure applied to the tuyere during blowing is increased. As a result, when the flow rate of the oxygen-containing gas increases during the period in which the flow rate of the oxygen-containing gas blown into the white rice fluctuates (that is, immediately after the start of the oxygen-containing gas blowing in the copper-making period), the furnace outlet of the converter The white cube blows up from. White glue blown up from the furnace mouth of the converter adheres to the furnace mouth of the converter, the smoke exhaust hood, and the exhaust heat recovery device. Hinders the operation of
[0007]
Therefore, it is necessary to prevent the blow-up phenomenon of white glue which occurs for a while immediately after the start of the oxygen-containing gas blowing in the copper making stage. Therefore, although the flow rate of the oxygen-containing gas in the oxygen-containing gas blowing is reduced to prevent the blow-up phenomenon of white glue, the problem is that the productivity of blister copper decreases because the progress of the oxidation reaction is suppressed. There is.
[0008]
[Problems to be solved by the invention]
The present invention solves the above problems, for example, in the case of copper smelting, increases the amount of molten mat to be charged into the converter to increase the amount of white mold in the copper making period, and white mold by oxygen-containing gas blowing. It is an object of the present invention to provide a converter operating method capable of preventing the blow-up phenomenon of copper and improving the productivity of blister copper.
[0009]
[Means for Solving the Problems]
The present invention relates to a converter operating method for producing a crude metal by accommodating a molten mat in a converter and performing oxygen-containing gas blowing, wherein the molten mat in the converter is oxidized by oxygen-containing gas blowing to form a white mold. Separated into slag, slag is removed, white mold is discharged from the converter, oxygen-containing gas is blown from the converter in the converter for a certain period of time, and the discharged white mold is converted into the converter. This is a converter operation method for oxidizing white glue to produce a crude metal by charging and blowing oxygen-containing gas.
[0010]
In the above-described invention, as a first preferred embodiment, 5 to 40% by mass of the white glue is discharged from the converter, and oxygen-containing gas blowing of the white glue in the converter is performed for 30 to 120 minutes. Thereafter, it is preferable to charge the white glue discharged from the converter into the converter.
In a second preferred embodiment, 20 to 30% by mass of the white glue is discharged from the converter, and the oxygen-containing gas is blown from the converter for 30 to 120 minutes. It is preferable to charge the discharged white glue to a converter.
[0011]
In a third preferred embodiment, the crude metal is preferably crude copper or crude nickel.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 is a layout diagram schematically showing an example of a copper smelting apparatus to which the present invention is applied.
The oxygen-containing gas blowing in the converter 1 improves the quality of the molten mat obtained in the flash smelting furnace (not shown). That is, a molten mat having a copper content of about 50 to 65% by mass obtained in a flash furnace is charged into a converter 1 from a furnace port 3, and a gas containing oxygen (for example, the atmosphere, oxygen-enriched air, or the like) is blown. An oxygen-containing gas is blown from the port 2 to produce blister copper having a copper content of about 97 to 99% by mass.
[0013]
This oxygen-containing gas blowing is roughly divided into a period in which slag is generated (so-called iron making period) and a period in which the quality of molten white glue in the latter stage is enhanced (so-called copper making period).
In performing oxygen-containing gas blowing during the sintering period, the converter 1 is tilted, and the molten mat in the ladle 7 is charged from the furnace opening 3 into the converter 1 using an overhead crane (not shown). Further, the converter 1 is erected and an oxygen-containing gas is blown from the tuyere 2. The perception period may be divided into a plurality of perception periods (for example, the first perception period and the second perception period, or the first perception period, the second perception period, and the third perception period). However, in each case, FeS in the molten mat is oxidized by oxygen in the oxygen-containing gas blown from the tuyere 2 so that the Fe component is separated into slag, the S component is separated into SO ₂ gas, and white glue ( That is, the reaction for producing the Cu ₂ S phase proceeds. When the oxygen-containing gas blowing in the cooking period (for example, the first cooking period and the second cooking period) is completed, the converter 1 is tilted to remove slag from the furnace port 3 to the slag ladle.
[0014]
After removing the slag in the final cooking period (for example, the second cooking period or the third cooking period), another white glue ladle is prepared in front of the converter 1.
Next, the converter 1 is tilted to discharge the white mold from the furnace opening 3 and temporarily stored in the ladle 7. If the amount of white glue discharged at this time is less than 20% by mass of the amount of white glue contained in the converter 1 after the removal of the slag, the white glue is blown by the oxygen-containing gas during the copper making stage described later. Blows up from the furnace opening 3. On the other hand, if it exceeds 30% by mass, the amount of white glue in the furnace is small and the reaction time is short, so that when the discharged white glue is recharged into the furnace, white glue may blow up. Therefore, the amount of white mold discharged from the converter 1 after removing the slag generated in the final cooking period is 20 to 30 with respect to the amount of white mold contained in the converter 1 after removing the slag. It is preferably within the range of mass%. In addition, the white glue may be discharged after the end of the first cooking period, or may be discharged after the completion of the second cooking period, and may be selected according to the operation situation.
[0015]
Next, in order to perform the oxygen-containing gas blowing in the copper making period, the converter 1 is erected, and the oxygen-containing gas is blown from the tuyere 2 into the white mold remaining in the converter 1. At this time, since the bath surface of the white glue remaining in the converter 1 is lowered, during the period when the flow rate of the oxygen-containing gas blown into the white glue fluctuates (that is, immediately after the start of the air blowing in the copper making period). Even if the flow rate of the oxygen-containing gas increases, it is possible to prevent white mold from blowing up from the furnace opening 3 of the converter 1. In addition, since the amount of white glue in the converter 1 is reduced, the hydrostatic pressure due to the white glue applied to the tuyere 2 is also small, and the load of a blower (not shown) for feeding the oxygen-containing gas to the tuyere 2 is reduced. The power consumption can be reduced.
[0016]
After blowing the oxygen-containing gas during the copper making period for 30 to 120 minutes in this way, the converter 1 was tilted back to the home position, the air blowing was stopped, and then the molten white glue stored in the ladle 7 was again removed from the furnace. Charge the converter 1 through the port 3. This white glue may be from the same converter 1 discharged, or may be charged from another converter 1. If the time required from the start of the blowing of the oxygen-containing gas in the copper making period to the reloading of the white glue stored in the ladle 7 is less than 30 minutes, the flow rate of the oxygen-containing gas in the oxygen-containing gas blowing becomes stable. Therefore, when the flow rate of the oxygen-containing gas increases, white glue blows up from the furnace port 3. On the other hand, if it exceeds 120 minutes, the white glue in the furnace is near the end point of the reaction, and the unreacted Cu ₂ S in the white glue recharged from the ladle 7 is oxidized intensively. It may blow up from the furnace opening 3. Therefore, the required time from the start of the oxygen-containing gas blowing in the copper making period to the reloading of the white glue stored in the ladle 7 is preferably in the range of 30 to 120 minutes.
[0017]
Thereafter, the converter 1 is erected, and oxygen-containing gas blowing is continued to produce blister copper.
In the present invention, even if the amount of the molten mat to be accommodated in the converter 1 is increased, the flow rate of the oxygen-containing gas immediately after the start of the oxygen-containing gas blowing in the copper making period fluctuates. The converter 1 can be operated without hindrance by preventing white rice from blowing up. Therefore, it is not necessary to reduce the flow rate of the oxygen-containing gas in the oxygen-containing gas blowing, thereby improving the productivity of blister copper. Moreover, since the amount of white mold in the converter 1 is reduced immediately after the start of the copper making period, the load on the blower that supplies the oxygen-containing gas to the tuyere 2 can be reduced, and the power consumption can be reduced.
[0018]
【Example】
In the dry smelting of copper, using a device shown in FIG. 1 (PS type converter, diameter 3960 mm, length 13000 mm 2), a molten mat having a Cu grade of 63% by mass was blown with oxygen-containing gas to produce blister copper. . That is, the molten mat obtained in the flash smelting furnace was charged into the converter 1 at 170 tons in the first sintering period and 50 tons in the second sintering period, and oxygen-containing gas blowing in the sintering period was performed. After removing the generated slag, 45 tons of white glue was discharged to ladle 7. At this time, the amount of white mold stored in the ladle 7 is equivalent to 24% by mass of the amount of white mold contained in the converter 1 after removing the slag.
[0019]
Next, oxygen-containing gas blowing in the coppermaking stage was performed on the white glue remaining in the converter 1 for 90 minutes. Thereafter, the white glue stored in the ladle 7 was charged into the converter 1 again by an overhead crane (not shown), and the oxygen-containing gas blowing in the copper making period was continued to produce blister copper. The average air volume at this time was 44100 Nm ³ / hr. This is an invention example.
[0020]
On the other hand, as a comparative example, the molten mat obtained in the flash smelting furnace was charged into the converter 1 in the same manner as in the invention example, and the oxygen-containing gas was blown during the fermentation period. After removing the generated slag, oxygen-containing gas was blown during the copper making stage to produce blister copper. The average air volume at this time was 42,800 Nm ³ / hr.
Therefore, in the present invention, it was confirmed that even if the amount of the molten mat charged into the converter 1 was increased and the oxygen-containing gas was blown, the blow-up phenomenon of white glue could be prevented without reducing the blown air volume. In addition, when the converter 1 is operated by applying the present invention, the amount of air blow increases, so that the time required for blowing the oxygen-containing gas during the copper making period is reduced, and the productivity is improved.
[0021]
【The invention's effect】
In the present invention, even if the oxygen-containing gas blowing is performed by increasing the amount of the molten mat to be charged into the converter, the blown copper can be prevented from blowing up without reducing the blown air volume, so that the productivity of blister copper is reduced. improves. In addition, since the amount of white mold in the converter is reduced immediately after the start of the copper making period, the load on the blower that supplies the oxygen-containing gas to the tuyeres can be reduced, and the power consumption can be reduced.
[Brief description of the drawings]
FIG. 1 is a layout diagram schematically showing an example of an apparatus to which the present invention is applied.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Converter 2 Tuyere 3 Furnace opening 4 Tilt device 5 Waste heat boiler 6 Movable hood 7 Ladle

Claims (4)

In a converter operation method for producing a crude metal by accommodating a molten mat in a converter and performing oxygen-containing gas blowing, the molten mat in the converter is oxidized by the oxygen-containing gas blowing to produce white glue and slag. After removing the slag, further discharging the white mold from the converter, performing the oxygen-containing gas blowing of the white mold in the converter, A method of operating a converter, comprising charging a white mold into a converter to blow the oxygen-containing gas and oxidizing the white mold to produce a crude metal. 5 to 40% by mass of the white glue was discharged from the converter, the oxygen-containing gas blowing of the white glue in the converter was performed for 30 to 120 minutes, and then discharged from the converter. The converter operation method according to claim 1, wherein the white glue is charged into the converter. 20 to 30% by mass of the white glue was discharged from the converter, the oxygen-containing gas was blown from the white glue in the converter for 30 to 120 minutes, and then discharged from the converter. The converter operation method according to claim 1, wherein the white glue is charged into the converter. 4. The converter operating method according to claim 1, wherein the crude metal is crude copper or crude nickel. 5.

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