JPS5896982A - Device for dissolving dust pellet - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for treating dust containing expensive metal elements generated during the operation process of a metal melting furnace such as a steelmaking furnace.
This invention relates to a dissolving device for dust pellets obtained by granulating this dust.

Dust generated from metal melting furnaces includes W, Ni, and No.

Expensive metal elements such as C'o are often contained in the form of oxides, and conventionally these dusts have been collected by suction using a dust collector. [Then, a method has been proposed in which this dust is granulated into pellets using a pelletizer, charged together with a carbon material into an electric furnace in which a molten metal is present, and reduced and melted in a reducing atmosphere to form an alloy. However, this method uses a resistance heating furnace.

In order to conveniently use an arc furnace, etc., a large amount of electricity will be required for Y$1.

Furthermore, it requires large-scale equipment that includes a complicated process of creating a reducing atmosphere inside the furnace. Therefore, there have been major difficulties in industrially putting it into practical use.

The present invention eliminates these drawbacks and reduces the metal elements in dust with a high metal recovery rate even on a relatively small scale, thereby saving resources by metallizing and reproducing a reusable alloy. It is an object of the present invention to provide a hot metal melting furnace.

The blast furnace method is an excellent method for reducing and dissolving ore Y. (Dust Hell) V When in-house processing is performed, the amount of dust generated is small, so the processing equipment is small-scale.

Pelletization is economically difficult to perform advanced processing and its quality is poor. When melting such dust pellets in a Y blast furnace, this blast furnace is /J1! If the temperature and its distribution are unstable, the dust pellets have low metal quality and generate a large amount of slag, which inhibits heat supply to the molten metal below and tends to solidify. Generally, in order to maintain stable operation in a blast furnace, K is required to have a grade of 50% or more in the ore. Furthermore, dust pellets have low strength and are easy to disintegrate, and while some of them turn into dust again, it is difficult to increase the particle size during granulation, which has a negative impact on the flow velocity distribution in the melting furnace, and the set flow velocity in the furnace must be set to a low value. It is necessary to For these reasons, the temperature at the bottom of the furnace tends to drop, making stable operation difficult. Furthermore, separation of metal from the low-temperature melt becomes incomplete.

The present invention is characterized in that the molten material dripped in a blast furnace type melting furnace is not stored at the bottom of the furnace, but is introduced into an adjacent heating chamber together with a blowing mountain-type combustible gas at melting furnace pressure. It also allows Y to flow easily and prevents a drop in temperature at the bottom of the melting furnace, and also maintains the temperature at a high temperature by burning this combustible gas with combustion-supporting gas pumped from another source to completely separate slag and metal. It is something you can do.

Next, the present invention will be explained with examples. The figure is a sectional view of a melting device according to an embodiment of the present invention. The dust pellet melting equipment consists of a melting furnace unit and a heating chamber 2. The dust pellet melting equipment consists of a melting furnace unit and a heating chamber 2.
It is lined. Melting furnace 1 is airtight with double bells at the top of the furnace! A charging device 3 capable of charging carbon materials mainly consisting of dust pellets and coke while holding them, and a top gas discharge port 4
Y: A plurality of tuyeres 5χ serving as combustion-supporting gas inlets slightly above the furnace bottom, and 6 inlets each for guiding the melt and furnace bottom gas into the heating chamber 1 at the lowest part of the inclined furnace bottom. There is.

The heating chamber 1 is communicated with the melting furnace 1 through an inlet 6, and has a combustion-supporting gas blowing lower, a combustion waste gas outlet 8, and a molten material outlet 9.

Carbon materials such as dust pellets and coke are charged alternately in the charging charge [5] to form layers and fill the furnace. Combustion-supporting gas such as air preheated by a preheating device (not shown) is blown into the furnace through the tuyere 5, where the carbon material is combusted and becomes combustion gas, most of which rises through the packed bed. The gas exits from the furnace top gas outlet 4. In this process, the dust pellets Y that have already been reduced are melted and dropped at the bottom of the furnace, and as they rise, the unreduced dust pellets are reduced and heat exchanged with the filling, and then they are discharged from the top gas outlet 4, as shown in the figure. The latent heat is used in preheating devices, etc.

The dust pellets and ash from the carbon material that melted and dripped at the bottom of the furnace reach the bottom of the furnace and flow down due to the slope, and the combustion gas at the bottom of the furnace flows into the inlet 6 where it is kept at a high temperature.
Because K flows through Y and into the heating chamber E, the bottom of the melting furnace is exposed to a blast of high-temperature combustion gas without stagnation of molten material, and a drop in temperature is prevented.

The gas ejected from the bottom of the melting furnace into the zero heat chamber is inlet 6.
Inside, the internal p-plane and the melt, which may be highly viscous at low temperatures, are also heated by their sensible heat, promoting flow and ejecting into the heating chamber 2. Pressurized combustion-supporting gas is blown into the heating chamber 1 from the combustion-supporting gas blowing lower by a pressure feeding device (not shown), and the melting furnace 1
The inside of the heating chamber is kept at a higher temperature than the bottom of the melting furnace, and the incoming low-temperature molten material is heated to completely eliminate separation due to the difference in specific gravity between slag and molten metal. do. combustion! The completed gas may be disposed of through the combustion waste gas outlet 8, or the sensible heat may be used for other appropriate purposes, but in order to control the amount of gas flowing from the bottom of the melting furnace into the heating chamber, the route is It is advisable to provide a suitable throttle valve Y inside. It is preferable that the combustion in the heating chamber E be of a weak reducing nature to prevent re-oxidation of the molten metal. The molten material that is heated in the heating chamber and separated into slag and molten metal is discharged from dedicated molten material discharge ports 9 and 9', which are normally blocked with clay, etc., and is cast in a ladle or at a foundry. However, the melt outlet may be shared.

Next, data examples of the embodiments described above will be shown. The dust pellets are granulated from the furnace system dust of the electric arc furnace. Melting furnace capacity 2.5 (pellets)/daff,
Coke ratio t2t (coke>/l <pellets), metal recovery rate 250-2yo Kg/l (pellets) This recovery rate is almost close to the theoretical value. Recovered metal analysis example (weight ratio) C
s5%, S=S<%# lMn52.5S, P S
CL4%, Siα04%* Ni54.5% m
Cr55.5% *W 115%MO112%e V
SO, S%, (:oHo, 4fb), and the operation was smooth from beginning to end.

The present invention as described above is a small blast furnace type melting furnace.
l! By sequentially discharging metals without allowing them to stagnate, operations can be stabilized, and metals can be recovered with high yield and low cost.

[Brief explanation of drawings]

FIG. 1 is a sectional view of the dust pellet melting device of the present invention. 1% melting furnace, heating chamber, 3 small charging device, 4 furnace top gas outlet, 5s impeller, 61 inlet, 7 combustion supporting gas inlet, 8
s Combustion waste gas outlet, 9 molten material outlet. 1 figure

Claims (1)

[Claims] The dust generated from a metal melting furnace, etc. is granulated into pellets, which are then melted into a melting equipment@, where a carbon agent mainly consisting of coke and the pellets are charged from the top of the furnace, and combustion-supporting gas is introduced from the tuyeres. Melting furnace row K for blowing and reducing and melting the pellets
[! Dust pellets consisting of a heating chamber that communicates with the bottom of the melting furnace through an inlet and is lined with a large material having a melt outlet, a combustion support gas inlet, and a combustion waste gas outlet. Melting equipment.