JPS6123249B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to an improvement in a process for continuously smelting impure copper in the molten phase.

In the conventional method, copper in the form of a melt was passed through a number of reaction chambers in a processing chamber in countercurrent to the heated gas, and in the process impurities were removed; Seen in the direction of flow - the last reaction chamber is supplied with fuel and oxygen gas-containing primary gas in substoichiometric proportions, and their combustion in the absence of oxygen produces a reduced heated gas. Furthermore, in this method, by additionally supplying oxygen-containing secondary gas in the reaction chamber that is present before the last reaction chamber, the fuel that has not yet been combusted and has been entrained in the heated gas is reduced. After-burning takes place.

The technical and economical advances achieved by this method further improve the process and make it more complete with the economy of fully automatic process control. phase/
Difficulties have been encountered in precisely regulating, at least quantitatively, the heat and mass exchange of metal melts.

In order to make it possible to control the reaction mechanism quantitatively, a controllable, reproducible, but in any case forced forcing between the reaction gas and the molten phase - copper/sludge is necessary. It is necessary to create and maintain convection and mass exchange conditions that occur naturally.

It is therefore an object of the present invention to improve the above-mentioned conventional copper smelting process in such a way that it can be carried out with a controllable reaction course both in terms of quantity and quality.

In order to solve this problem, the present invention proposes the following.

The secondary gas is directed approximately perpendicularly onto the surface of the essentially bare metal bath in the form of at least one energy-rich radial stream of gas focused by an accelerating nozzle before being combusted with a heated gas containing fuel. The secondary gas is blown into contact with the above-mentioned surface such that a constant mass transfer from the gas to the metal bath takes place, and the secondary gas is brought into contact with the above-mentioned surface so that the blown pressure present at the junction of the gas radial flow is centered on the We proposed that a laminar flow of the melt rotating in an annular shape be injected with a radiation force large enough to produce a reaction unit with a constant mass transfer, which is divided by the convective state of the system together with a gas radiation flow. do.

The above method is of great significance, since the gas radial stream is forced into contact with the metal bath, displacing the suspended sludge layer, and in a manner that allows the flow density to be regulated, and in this case the gas radial stream is separated by extremely rapid convection field of liquid metal that occurs at a point.
This is because a controllable exchange of substances takes place.

By means of the above-mentioned method, it is possible to obtain an advantageous, particularly rapid reaction course which can therefore be readily defined by the magnitude of the process control made possible by a constant energy.

The reaction of the liquid copper with the reactant gas essentially takes place within the injection position due to the gas dam of the bath, and the surface size at this injection position can be measured, but Since the temperature can be adjusted and kept constant, the state of mass transfer can be quantitatively controlled. This is another advantage of the invention over known methods, namely the possibility of programmable control of the copper smelting process.
In this case, care must be taken to prevent the bath from "splattering" in order to prevent disturbances, which occur, for example, when bath movements are too vigorous. This is because, on the one hand, the equilibrium of the reaction regulated by this "splatter" and thus the regulatory capacity is disturbed, and on the other hand, at least locally, overoxidation phenomena occur with the formation of copper oxide. These two phenomena are undesirable.

A final method according to the invention is to adjust the radiation force and the distance of the nozzle orifice from the bath surface, depending on the type of reactant gas used, so that the metal bath does not actually splash.

The invention will be described in more detail below with reference to the embodiments illustrated in the accompanying drawings.

FIG. 1 shows a rectangular melting furnace 1. This melting furnace has three bucket-shaped reaction chambers 5,
It is divided into 6 and 7 parts. In the partition wall 2 there is a flow groove 9 for copper in the form of a melt. Bath condition 1 in reaction chamber 6
0 is accepted. A liquid copper bath 11 exists below this bath level, and a sludge layer 12 exists above the bath level. Openings 13 in the furnace wall serve to remove the sludge 12 from the scouring-reaction chamber 6 in which the oxidation takes place. code 1
It is supplied into the furnace 1 in the form of a melt at the position 4, and is supplied with the reference numeral 15.
A partition plate 8 serves to retain the sludge at the outflow end of the reaction chamber 6 in the flow direction of the copper leaving the furnace 1 after scouring at the position . The liquid copper passes through the flow port 16, which has a bath level of 10 or less, and passes through the partition plate 8. Reaction chamber 5
Closable openings 17 in the furnace wall serve for the storage and supply of solids, such as copper concentrate and/or fuel, and the exhaust gases leave the furnace 1 through the chimney 19. A burner 36 is provided on the closed side of the end wall 18 for heating. During operation, the furnace 1 is supplied with liquid blister copper at 14 and/or with copper concentrate and fuel at 17. In zone 5' the heating of the material is increased to a processing temperature suitable for subsequent scouring. In the zone 6, the oxygen-containing reaction gas is blown in the form of a concentrated, energy-rich gas radial stream 21 via the nozzle rod 20 onto the bath surface 10 of the molten copper 11. A throttle valve 22 in the neck 23 of the nozzle rod 20 serves to control the inlet and emitted energy. Surface 1 of copper bath 11
At 0, the blowing pressure 24 is clearly visible.
This blowing pressure 24 has the shape of a concave bowl.
In the vicinity of this blowing pressure, the dynamic pressure of the diverted gas radial stream 21 forces the sludge layer 12 laterally away from the copper molten bath 11. This phenomenon is shown enlarged in FIG. 2, based on what was observed experimentally.

The opening 25 in the nozzle bar 20 is visible. . A gas radiant flow 21 is discharged from this opening 25, and the sludge layer 12 above the molten bath 11 is
I run into it. The dynamic pressure of the gas radial stream 21 in the deflection area 26 pushes back the sludge layer 21 . An "eye" 28 is formed on the bare surface of the molten bath 11 and below this eye 28 - indicated by the line A--B - a bowl-shaped concave blowing pressure 24 is created in the metal molten bath 11. . The diverted gas flows back into the surrounding chamber at 29. gas radial flow 21
excited by contact with and its traversal force,
Under the influence of the rising force in the vicinity of the blowing pressure 24 in the melt 11, a strong bath turbulence occurs in the form of an annular flow zone, as indicated by the torque 27 in the flow direction.

In FIG. 1, another nozzle rod 30 can be seen in the reaction chamber 7 for blowing the reaction gas into the copper bath. This nozzle rod 30 has two connections 32 and 33 at its head, 32 of these connections being for the supply of carrier gas and the other 33 for supplying fuel such as diesel oil, natural gas, propane, lime powder. It is intended to supply the following. Throttle valve 34,3
5 serves to regulate the pressure and thus the energy and flow density of the gas radial stream.

Next, the embodiments of the method according to the present invention will be described as follows.

According to the invention, the discharge force and the distance of the nozzle orifice from the bath surface 10 are adjusted, depending on the relatives of the reactant gases used, so that the metal bath is practically not splashed.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view of the furnace apparatus used in the present invention, and Fig. 2 is a view showing the opening of the nozzle rod, together with the sludge layer, which emits a radial stream of gas onto the copper molten bath located below the nozzle rod. . The symbol in the figure is 11...metal bath.

Claims (1)

[Scope of Claims] 1. Copper in the form of a melt is guided in a processing chamber through three reaction chambers in countercurrent to the heated gas, during which impurities are removed and - viewed in the direction of flow of the melt - the final Fuel and oxygen-containing primary gas are supplied to the reaction chamber at a sub-stoichiometric ratio, and their combustion in the absence of oxygen produces a reduced heating gas, which is then fed into the reaction chamber before the last reaction gas chamber. This is a method for continuously smelting impure copper, in which after-burning of the fuel entrained in the heated gas without further combustion is carried out by additionally supplying an oxygen-containing secondary gas. The supply of at least the secondary gas is carried out in such a way that the secondary gas is first brought into contact as a reaction gas with the melt phase of the metal bath 11 in such a way that a constant mass transfer into this metal bath 11 takes place, and then for the first time here. In a method for continuous smelting of impure copper in which the secondary gas is combusted with a heated gas, the secondary gas is combusted with at least one energy-rich gas focused by an accelerating nozzle 20 before being combusted with the heated gas containing fuel. Blowing in the form of one gas radial stream 21 approximately perpendicularly onto the surface 10 of the essentially bare metal bath 11 so that a constant mass transfer from the gas to the metal bath 11 takes place. contacting and introducing the secondary gas into an essentially annular rotating laminar flow 2 of the melt about the blowing pressure 24 present at the branch point 26 of the gas radial flow 21
7, together with the gas radiation stream 21, is injected with such a large radiation force as to produce a reaction unit with a constant mass transfer, delimited by the convective conditions of the system.