JPS63118021A - Method and apparatus for regenerating metal and alloy - Google Patents

Abstract

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

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for regenerating metals or alloys, especially iron alloys, by reducing metal oxides in a reduction zone formed by a bed of coal through which a reducing gas flows. and apparatus for carrying out the method.

PRIOR ART European Patent Publication No. AO 174291 discloses a method for melting metals such as copper, lead, zinc, nickel, cobalt and tin from fine oxidized metal ores that do not contain iron. There, the charge material is charged into the reduction zone formed by the coal fluidized bed in the melter-vaporizer. The oxide charge material passes through a reduction zone and is reduced to metal, which is collected in the lower part of the melt vaporizer.

Although the method disclosed in European Patent Publication No. AO 174291 is advantageous when used to reduce oxides by reacting with elemental carbon at temperatures below 1000°C, Metals and alloys, especially manganese-iron, which can only be regenerated from their oxides above 1000°C using elemental carbon as the reducing agent because of the relatively short contact time of the particles with the oxide-loading material that reacts at high temperatures. Various problems have been shown to occur when reclaiming iron alloys such as chromium iron and silicon iron.

(Objective of the Invention) The present invention aims to solve the above-mentioned drawbacks and problems, and as mentioned above, in a melt vaporizer, a fine particle oxide charge material is processed to the extent that it reacts with simple carbon only at a temperature of 1000°C or higher. A method and apparatus for regenerating metals and alloys with a strong affinity for oxygen, particularly iron alloys such as manganese iron, chromium iron, and silicon iron, is provided.

Arrangements of the Invention To achieve the above object, the method of the present invention comprises a bottom layer consisting of degassed coal covering a sump of reduced metal and slag, oxygen or an oxygen-containing gas being introduced so as to substantially and a top layer into which a combustion gas consisting of carbon particles and oxygen or an oxygen-containing gas is introduced. This is done by forming a stationary coal bed.

Advantageously, the bulk oxide loading material has a particle size of 6 trtm or less.

Coal suitable for forming each stationary bed layer has a particle size of 5 to 10
0 mm, especially 5 to 30 zz.

In a preferred embodiment, the middle static bed layer and the top static bed layer have a thickness of 1 to 4 shoulders.

A pond embodiment of the inventive method separates dusty carbon particles from the exhaust gas passing through the reduction zone and feeds these dusty carbon particles, preferably in a heated state, to each burner directed to the top static bed layer. It is characterized by:

The exhaust gas, which has been liberated with carbon particles, is used as a transport medium for the particulate oxide charge.

The coal preferably maintains a lump shape even after degassing, and has a particle size of 5 to 100 μm, preferably 5 to 30 μ,
At least 50% of the degassed coal formed after deaeration has a particle size of 5 to 10011 nm or 5 to 30 nm, and the remainder is finer grains.

The method of the present invention involves countercurrent heat exchange, metallurgical reaction with carbon alone in a stationary bed necessary for reduction of non-noble metal oxides, and metal and slag reduction treatment in a blast furnace heated by fossil energy. The advantage is that all known advantages are maintained, such as good separation. Coking or degassing of coal can be done without forming tar and other condensable compounds. The gas produced during deaeration of coal acts as a reducing agent for the reducing gas produced by gasification of the deaerated coal.

In another embodiment, the charged oxide material is pre-reduced in a pre-reduction step, which is very advantageous when producing ferrous alloys. In the pre-reduction step, the iron oxide portion of the charged material is subjected to this pre-reduction.

A particular advantage of the above method is that non-noble metal oxides, such as silicon, chromium, manganese, etc., can be reduced without using electrical energy. In the method of the invention, the energy required to degas the coal is controlled by simple means. This is because small particle sizes of 5 mm or less are discharged with the hot gas from the melter-vaporizer, separated, and returned to the upper blowing region of the oxygen-containing gas, where they are oxidized by the oxygen-containing gas and release heat. This is because that.

In the particle decomposition reaction, coal with a particle size fraction of 16 to 2Qma
The chamber is preheated to 00'C and degassed for 1 hour. The volume of the chamber is 12
It is considered to be dm3. After cooling with a cold inert gas bath, the particle distribution is measured.

A blast furnace type melting and vaporizing apparatus lined with a refractory material for carrying out the above method of the present invention has a loading port for introducing coal and a gas discharge duct in the upper part, and a carbon particle and a supply duct for supplying oxygen or an oxygen-containing gas, with a refractory lining in the lower part for collecting molten metal and liquid slag. This device has three stationary bed layers A, B, and C arranged in a stacked manner.
In the area between the bottom stationary bed layer Δ and the middle stationary bed layer 8? Qf
A blowing pipe for oxygen or oxygen-containing gas is provided in a ring shape, and a plurality of blowing pipes for fine oxide charging material are provided in a ring shape slightly above the blowing pipe for the oxygen or oxygen-containing gas, and then, slightly above the intermediate stationary bed layer B and the top stationary layer B. It is characterized in that a plurality of burners are provided in the area between the bed layers C to supply carbon particles and oxygen or oxygen-containing gas.

It is further advantageous if the gas discharge tact is equipped with a thermal centrifugal separator to separate carbon particles from the exhaust gas, and the discharge end of the thermal centrifugal separator is fluidly connected to each burner arranged in a ring.

In another embodiment, the thermal centrifuge includes a second
Thermal centrifuges are connected in an AL system, and a charger for oxide loading material is provided in the connection tact between the centrifuges, and the discharge b:f'i part of the second thermal centrifuge is connected to the transport takt. It is connected to each pipe for blowing oxide-loaded material arranged in a ring shape through the pipe.

(Example) The method of the present invention and the apparatus for carrying out the method are
This will be explained in more detail using the drawings.

The blast furnace melter-vaporizer designated with l has l refractory lining 2 . The bottom area of the melter vaporizer serves to accommodate molten metal 3 and molten slag 4. The tap opening for metal is shown with the reference numeral 5, and the tap opening for slug is shown with the reference numeral 6. In the upper part of this melter-vaporizer, a loading lower for supplying lump coal and a loading port 9 for bulk oxide charge material are provided.

Above the reservoirs 3 and 4 there is a static coal bed, i.e. a bottom layer A consisting of degassed coal through which no gas passes, an intermediate layer B consisting of degassed coal stacked on said bottom layer A, and said intermediate layer B
A top layer C is formed consisting of coal particles stacked on top of each other and through which the gas passes.

A plurality of blowing pipes 8 for oxygen or oxygen-containing gas are arranged in the form of a ring through the side wall of the melter-vaporizer 1 . These pipes are provided in the boundary area between the stationary bed layer A and the stationary bed layer 8 through which gas does not pass. A plurality of nozzle-shaped blowing pipes 9 are installed in a slightly upper part of these ring-shaped blowing pipes 8, that is, between the middle part and the upper part of the middle stationary bed layer B.
are inserted in a ring-shaped arrangement, and the fine oxide charge is introduced into the intermediate layer B through these blowing pipes 9 at a portion slightly above the ring-shaped blowing pipes 9, that is, between layers B and C. A plurality of burners 10 penetrating the side wall of the melter-vaporizer I are arranged in a ring shape in the boundary area. A mixture of empty carbon particles and oxygen or an oxygen-containing gas is introduced into these burners 10 . A gas discharge duct (11) led out from the upper part of the melter vaporizer l transfers the generated exhaust gas to a thermal centrifuge 12.

The empty carbon particles suspended in the exhaust gas are removed by thermal centrifuge 1.
2 and then fed from the discharge end of a thermal centrifuge 12 provided with metering means 13 via a duct 14 to each burner 10 arranged in a ring. The duct for oxygen-containing gas connected to each burner 10 has the symbol 1
5 is attached and shown. By means of the metering means 13, the degree of filling of the thermal centrifuge 12 can be adjusted to control the separation effect of the thermal centrifuge 12. The exhaust gas is led from the upper part of the thermal centrifuge 12 to a second thermal centrifuge 17 via a tact 16. A loader 18 is inserted into the connecting duct 16 and is loaded from a bin 19 storing fine oxide charge material.

The gas obtained from tact 16 acts as a transport medium. The fine oxide charge material is discharged from the discharge end of the thermal centrifuge 17 into a transport duct 20 from which it is fed to the blow pipe 9 via a duct h21.

A duct 22 leads out from the upper end of the thermal centrifuge 17, through which excess exhaust gas is discharged. The excess exhaust gas is cooled, compressed and blown via duct 23 into duct 21 as transport medium.

In the process according to the invention, it is advantageous if the coal charged in the upper part of the melter-vaporizer I is degassed in a stationary bed layer C. The amount of heat required for deaeration is supplied by the thermal reducing gas rising from the stationary bed layer B, and also by the heat of combustion obtained by burning solid carbon particles with oxygen-containing gas in each burner IO. The vertical length of Ic is chosen to be the minimum temperature of the gas leaving layer C, or 950°C. This ensures the decomposition of tar and other condensable compounds.

In this way, the stationary bed layer C is prevented from closing. The thickness of this stationary bed layer C is preferably 1 to 4 m.

It is also advantageous if the vertical length of the stationary bed layer B is 1 to 4+.

The degassed coal in the stationary bed layer C sinks to form the stationary bed layer B.

The fine-grained oxide charge material is pre-reduced by the thermal reducing gas and fine dust in the second centrifugal separator 17 and reseparated from the gas. Loading the thermal reducing gas together with the contained dust can sustain the strong reduction of the hot gas obtained from the melt vaporizer l.The fine oxide loading material is separated after pre-reducing by the fine dust. Notification B
is melted and reduced by simple carbon. The heat required for melting and reduction is supplied by vaporizing the hot degassed coal by means of an oxygen-containing gas introduced into the vaporizer via the blow pipe 8.

The molten metal and molten slag formed in stationary bed layer B flow downward and are collected and tapped below stationary bed layer A.

FIG. 2 shows a temperature distribution diagram with respect to the height of the melter-vaporizer 1, in which the height conditions are plotted on the ordinate and the temperature scale is marked on the abscissa. Here, the temperature change of the coal charge is shown as a solid line, and the temperature change of gas formation is shown as a dashed line. 8 is the height of the ring of the blowing pipe 8, 9 is the height of the blowing vibe 9 for fine oxide loading material (ore), 10 is the height of the ring of the blowing pipe 8;
denotes the height of the carbon particles recirculating through the burner 10, 24 the height of the static bed upper limit 24, and 11 the height of each gas iJE outlet duct 11 and coal loading lower.

[Brief explanation of the drawing]

Figure 1 shows a melting vaporizer equipped with the accessory equipment according to the present invention.
FIG. 2 is a temperature distribution diagram in the melter-vaporizer. l...Blast furnace type melting vaporizer, 2...Refractory lining,
3... Molten metal reservoir, 4... Molten slag reservoir, 5... Tap port for metal, 6... Tap port for slag, 7... Loading port for coal, End... For oxygen or oxygen-containing gas. Blowing vibe, 9
Nozzle type blow pipe, 10... burner, 11.
... Gas discharge duct, 12 and 17 ... Thermal centrifuge, I3 ... Metering supply means, 14.16.21.22 and 23 ... Duct, 15
...Oxygen-containing gas duct, I8...Loader, 19
...Bin, 20...Transportation duct, 24...Upper limit of stationary coal bed, A...Bottom stationary coal bed layer, B...Intermediate stationary coal bed layer,
C...One stationary coal bed at the top. Patent Applicant Hoestoralpin Akchengesernjaft Representative Patent Attorney Haka Aoyama (1 person) FIG. 2 1.11 □ □

Claims (11)

[Claims] (1) A bottom consisting of degassed coal covering a sump of reduced metal and slag for the regeneration of metals and alloys by reducing metal oxides in a reduction zone formed by a bed of coal through which reducing gas is passed. Three stationary coal bed layers, a stationary bed layer, an intermediate stationary bed layer, and a top stationary bed layer, are provided, and oxygen or an oxygen-containing gas is introduced into the intermediate stationary bed layer to produce a thermal reduction gas consisting essentially of CO. At the same time, a fine oxide-loaded material is introduced into the intermediate stationary bed layer from a position a little distance upward therefrom, and a combustion gas consisting of carbon particles and oxygen or an oxygen-containing gas is introduced into the top stationary bed layer. methods for recycling metals and alloys. (2) The method according to claim 1, wherein the particle size of the bulk oxide loading material is 6 mm or less. (3) The method according to claim 1, wherein the three stationary coal bed layers are formed from coal having a grain size of 5 to 100 mm. (4) The method according to claim 3, wherein the particle size of the coal is 5 to 30 mm. (5) The thickness of the intermediate stationary bed layer and the top stationary bed layer is 1 to 4
2. The method of claim 1, wherein the method is maintained at m. (6) The exhaust gas is passed through a stationary coal bed forming a reduction zone, and the dusty carbon particles are separated from the exhaust gas and the carbon particles are sent together with oxygen or oxygen-containing gas to a burner directed toward the top stationary bed. A method according to claim 1 for providing. (7) The method according to claim 6, wherein the separated carbon particles are supplied to a burner in a heated state. (8) The method according to claim 6, in which exhaust gas from which carbon particles have been liberated is used as a transport medium for the fine oxide-loaded material. (9) A blast furnace type melting vaporizer lined with a refractory material and having an upper part, a side wall, and a lower part, a loading port for loading coal and a discharge duct for exhaust gas are provided in the upper part of the melting vaporizer, and a side wall of the melting vaporizer; A supply duct for supplying carbon particles and oxygen or oxygen-containing gas is provided through the melter-vaporizer, and a collection section for molten metal and molten slag is provided in the lower part of the melter-vaporizer, formed by a coal bed through which reducing gas passes. In an apparatus for regenerating metals and alloys by reducing metal oxides in a reduction region, three stationary coal bed layers are provided in a stacked manner to form a bottom stationary bed layer, an intermediate stationary bed layer, and a top stationary bed layer. A plurality of blowing pipes for blowing oxygen or oxygen-containing gas are provided in a ring shape in the area between the bottom static bed layer and the intermediate static bed layer made of degassed coal so as to cover the liquid pool of degassed metal and slag. a plurality of blowing pipes for loading fine oxide charging material are provided in a ring shape at a position spaced upward from the arrangement part of the oxygen blowing pipe, and for blowing the charging material. A plurality of burners for charging carbon particles and oxygen or an oxygen-containing gas are provided in a ring shape in a region between the intermediate stationary bed layer and the top stationary bed layer that are spaced upward from the burner arrangement part. playback device. (10) A patent in which an exhaust gas exhaust duct is provided with a thermal centrifugal separator for separating carbon particles from the exhaust gas, and a fluid connection means for connecting the discharge end of the thermal centrifugal separator to each burner arranged in a ring shape. The apparatus according to claim 9. (11) a second thermal centrifuge having a discharge end; a connecting duct fluidly connecting the thermal centrifuge and the second thermal centrifuge; loading means for supplying oxide-loaded material to the connecting duct;
and a transport duct connecting the discharge end of the second thermal centrifuge and each oxide charge blowing pipe arranged in a ring.