JPS586253A - Dust separator - Google Patents

Abstract

PURPOSE:To separate magnetic materials from dust in waste gases from steel making furnaces by placing a member made of a magnetism permeable and nonmagnetic material on the outer or inner side of a magnet and adsorbing magnetic dust by magnetic attraction then parting the magnet. CONSTITUTION:In a device of separating magnetic dust and nonmagnetic dust from steel making furnaces, a magnetic body 4 made of a nonmagnetic and magnetism permeable material is placed on the outer or inner side of a magnet 5. The magnetic dust in the waste gases is attracted and catpured to the body 4 by the magnetism of the magnet 5. When the amt. of adsorption increases, the magnet 5 is parted therefrom to release the magnetic field and therefore the dust falls by gravity. In this way, the magnetic materials are separated and recovered by the simple method.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for separating magnetic materials from dust including saponified metals entrained in gas discharged from a steelmaking furnace. This relates to a device that demagnetizes dust by letting it pass.

In addition to gases such as marron monoxide, carbon dioxide, nitrogen, and hydrogen, gases from steelmaking fi4 such as blast furnaces, converter furnaces, arc furnaces, and cupola furnaces are produced!・, 艷04, Ni Fe2O4, Mn Fe1
Magnetic dust such as 04, and Fog (4, 8 to Za
i(4, OaO.

Exhaust gas containing dust of non-magnetic substances such as Aya θ and PbO is generated. If this exhaust gas was emitted as is, it would be impossible to
Since the dust contaminates the HI, it is collected by dust collection equipment. If the 1ini dust thus collected is discarded as it is, it will cause secondary separation, so it will be discarded after being subjected to a certain degree of asahi ring. In recent years, there has been an increase in the number of attempts to reuse it, for example by reducing and reusing it as a raw material for iron manufacturing, or by reducing it with nitrogen to recover zinc and zinc white. However, this % ring was large-scale and costly. On the other hand, since the various components of the collected steelmaking dust wire are geometrically and physically mixed together, it is extremely difficult to separate them, and the separation cost is high. , it is currently not possible to separate and recover component m. Nowadays, there is a strong demand for resource saving, and a simple separation and recovery method is strongly desired.

In order to meet these demands, a method has been proposed in which iron and iron oxide dust is separated by direct contact with solid particles at high temperatures, and then the carrier gas is cooled to solidify and separate the nonferrous metals ( JP-A-55-50440). However, this method requires large-scale equipment and has the disadvantage of poor separation performance relative to cost.

Therefore, the inventors of the present invention have repeatedly studied some electricity distribution methods that eliminate the above-mentioned drawbacks. As a result, the steelmaking dust that has been partially collected by the dust collector cannot be separated by magnetism anymore because each component is entangled with the dust.
We discovered that if the dust components are captured by a single aircraft and are on their way before being blown away by Hofno, they fly relatively independently and are easily separated by magnetism.Based on this, we filed a patent application for a magnetic separation method for dust.

Such magnetic separation of dust particles is achieved by placing a magnetic field generator (hereinafter referred to as a magnet) in the path of the discharged dust, and separating dust consisting only of a magnetic material and dust consisting of a magnetic material and a magnetic material attached thereto (hereinafter referred to as a magnet). The device used for this is a device that separates the magnetic transporters and non-magnetic particles in the dust by changing their flight trajectories, and is directly connected to a collector. Examples include rotating disk devices using permanent magnets used in the water treatment field, but we have found a device with a structure that efficiently separates the attracted magnetic dust from the magnet and collects it, which is satisfactory. It has not been.

The present invention was achieved as a result of various studies with the aim of solving these problems in magnetic separation of dust, and instead of attaching magnetic dust in exhaust gas directly to a magnet, it uses magnetic separation. Place a member made of a non-magnetic material on the outside or inside of a magnet, indirectly attract magnetically to attract the magnetic dust F to the surface of the member, and after the removal, move the magnet away from the member. This is a separation device that allows the magnetic dust on the surface to fall and collect the magnetic dust. That is, the present invention provides an apparatus in which exhaust gas from an H4 furnace containing a magnetic material passes through an exhaust gas passage system in which a magnetic field gradient is generated, and is separated into magnetic dust and non-magnetic dust. Either a magnetic filter and permeable plow body with a magnetic material removably installed inside the exhaust gas passage system, or a magnetically permeable cylinder with a magnetic field gradient forming material removably installed on the outside. The body itself serves as a thread for the exhaust gas, and the O-based dust in the exhaust gas is adsorbed on the outer surface or inner surface of these cylinders,
II/! A dust separator configured to separate and collect the magnetic field gradient forming material from the outer surface or inner surface of the cylinder by releasing the magnetic field by separating the magnetic field gradient forming material from the cylinder. This is the purpose.

The present invention will be explained below based on the drawings.

FIGS. 1 and 2 are a partially cutaway overall @ perspective view and a partially enlarged perspective view, respectively, showing an example of the dust separation device of the present invention. In the figure, (2) is a chamber installed in the middle of a duct (1) for exhaust gas from a steelmaking furnace, etc., and a large number of cylindrical bodies (4) pass through the upper JE (3) of the chamber and enter the chamber (2). Exhaust gas passage r:,! It is fixed vertically and facing downwards. ω) is a vertically long rod-shaped magnet that can be inserted into and pulled out from each of the plurality of cylinders (4), and this is a magnet that is installed vertically on the top of the upper base (3). (6) A manual handle (8) attached to a frame (7) installed horizontally above the barge and a rotating roller (9) directly connected to the hoist are used to hoist the boat with lobes (not shown) or the like, and spring and unload it. By doing so, it is made to move up and down within the cylindrical body (4).

(to) is a striking angle attached to the framework (7) and is provided in contact with a plurality of plow bodies (4).

(3a) This is the l plate that covers the winding up and unwinding mechanism of these magnets (6). A windshield board that allows exhaust gas to pass through the air overnight (
2) is a hopper installed on the bottom, and a dust packet trout for collection is attached to the tip of the hopper.

In the above configuration E, the cylinder θ) has a cylindrical cross-sectional view as shown in 2111), a rectangle as shown in FIG. 2), or any other arbitrary shape. It is something. However, the material is non-magnetic and has magnetic permeability, so the magnetism inside it (the inserted koji magnet) is
The magnetic material contained in the exhaust gas is adsorbed on the outer surface of the material, such as aluminum, plastic, etc.
It must be made of brass, copper, natural or synthetic rubber, etc. For example, as shown in the cutaway diagonal views of FIG.
A large number of magnets (58) are attached to the yoke (6b).
An example is a structure in which the JIl poles are used as anti-debris magnetic fields (1'jli comrade, or 8 poles are used as a counter-waste magnetic field) and are stacked alternately to spread the magnetic field.

In a dust separation device such as a board, when gas discharged from a steelmaking furnace, etc. is passed horizontally in the direction of the arrow from the entrance (1 m) of the chamber, the exhaust gas is obstructed by the ventilation board (b). Among the dust that is contained in the exhaust gas and entrained, only magnetic particles are removed by a non-magnetic cylindrical body installed vertically inside the chamber.
) Due to the magnetism of the magnet () inserted inside the cylinder)
The slurry is trapped on the outer surface of the However, the uncaptured magnetic material flows from the exhaust gas outlet (to the exhaust gas outlet) to the chamber (
The dust goes outside and is caught and collected by a known dust collecting device such as a bag filter (not shown). When the amount of magnetic dust adhering to the outer surface of the cylinder 1) becomes ◆, rotate the roller @) through the handle (8) until it reaches -(9).
) with the wire (intestine &) wrapped around the magnet 俤) into the cylindrical body O)
When the cylinder C) is rolled up and the magnetic field is released, the magnetic dust adhering to the outer surface of the cylinder C) falls under its own weight.

Furthermore, the angle bracket provided in contact with the cylinder (4) is struck with a hammer or the like to shake off the remaining magnetic dust that has adhered to the outside of the cylinder (0) without falling. The magnetic dust is collected in a dust packet (b) provided at the tip of the hopper. As described above, the dust separator of this embodiment attracts magnetic dust through a magnetically permeable non-magnetic body (cylindrical body) so that the exhaust gas and the magnet do not come into direct contact with each other in the duct passage. When separating and recovering the magnetic dust, the structure is such that the magnet is separated from the non-magnetic material.
lkfIi' can be performed efficiently.

FIG. 3 is a perspective view showing a modified example of the cylindrical body in the dust separation device of the present invention, in which magnet blocks (Sm) and yoke blocks (ib) are arranged alternately on the outside of the cylindrical body (4) as described above. A U-shaped columnar magnet (5) is stacked on top of the
Since it is attached removably as shown in the figure, the exhaust gas is allowed to pass through the cylinder (4) itself in the direction of the arrow Q, so that the magnetic dust F is adsorbed inside it, and when it is separated and collected, It has a structure in which the magnet (4) is separated from the cylinder (4) by another wave-like means. In this example, if the cylindrical body 0) is made of a flexible material such as cloth or soft plastic, the magnet (5
) is mounted on the outside, the cylindrical body 0) becomes bellows-shaped as shown in Fig. 5, and the adsorption area of the magnetic dust F on the inside becomes smaller. A durable material such as aluminum may also be used.

The steelmaking dust separated by the apparatus of the present invention is the dust contained in the exhaust gas from the steelmaking furnace as described above, and is F
a, l1eO, Fe, Q,, 1@OB, ZmC im 81 (~, CjaO%Nio, ml, C%, PbC4
,0rlOi ,(3d(4Mg().

It contains Na, (4KH2, Na1l, K(31, etc.) as constituent components, and it varies depending on the type of steelmaking furnace and the operating conditions of the furnace, but the device of the present invention uses dannetite (Fes).
Contains magnetic and non-magnetic substances such as
We will meet at Gin application. Exhaust gas from a steelmaking furnace is usually 100G'I
At high temperatures above 0.0 O, zinc and other ferrous metals from ships are in the form of steam, and when they leave the steelmaking furnace and are combusted as combustible gases in combustion towers, they become the oxide dust described above.

Next, the exhaust gas is cooled down to about 200℃ in a cooling tower. High temperatures higher than about 300℃ are undesirable because the magnetization of the magnetic material decreases. Through these processes, iron oxide and long iron metal oxide are Uniquely shaped crystals, for example, ji+aO, are needle-shaped with a length of 1 μ or more (other crystals are spherical,
It is entrained in the exhaust gas and led out to the exhaust gas passage system. If this dust is captured as it is by the dust collector llIc, the various components become entangled in a complicated manner and the magnetic material cannot be separated by the magnetic material 9jc#c. However, the dust separation device of the present invention installed in the middle of the exhaust gas passage system magnetic dust and non-magnetic dust are separated.

Next, as an example of a method of separating dust in exhaust gas using the dust separator of the present invention, a case where exhaust gas from an arc furnace is treated [step-out to 70-sheet and # in Figure 4] will be described. The exhaust gas from the arc furnace (M1) is flammable (F'l).
'), the CO acid component in the gas is burned, and the iron and steel metal are oxidized.6 Next, it is cooled to about 200℃ in a cooling tower (CT), and passed through a duct (1) for magnetic separation. The dust enters the ring, where the dust containing a high concentration of magnetic material is separated. Zinc is recovered from the cuttings. On the other hand, dust containing a high concentration of magnetic material is put into a re-magnetized atomizer (MA), where it is converted to dust containing a higher concentration of magnetic material, and J! It is separated into dust (containing dust) (11 and 11), and the former dust is used for medium and low-grade magnets, raw materials for 7-elite, red iron for end-stopping, etc.

The surroundings of the magnetic separation device (2) may also be configured as shown in FIG. In other words, when you open the valve (vine), the duct (1)
Exhaust gas is introduced through a valve ( Vl) and enters the dust collection 1fIkO. This magnetic separation device! While operating the wheel, the valve (Vs) ('%) ('
%) is in a closed cane state. Also, a magnetic separation device! When brushing off dust containing a high concentration of magnetic material adhering to cormorants, close the valve ('v1) (vine) and close the valve (ma4) (
vl) is opened, the magnet is moved away from the exhaust gas passage system to release the magnetic field, and then the valve (vl) is opened to allow air flow to be introduced between the magnetic separators through the air tank (barrier), while backflow exhaust gas is passed through the valve (eagle). ) and enters the cyclone 0) or bag filter -), where das) (to) is compensated,
149 to the valve) and enters the dust collector 114Q. Dust is used for medium- and low-grade magnets, ferrite raw materials, rust prevention pengara, etc.

As described in detail above, the present invention provides a method for attaching and detaching a magnet to the exhaust gas passage in an apparatus that generates a magnetic field gradient and uses magnetic force to separate steelmaking dust before the dust collection process. A non-magnetic magnetically permeable member is attached to the surface of the dust, and the magnetic substance in the dust is attracted to the surface of the dust via the magnetically permeable member. - It is amazing that it can be separated and collected extremely easily by simply removing the magnetic field and shaking it off.In addition, the separated dust can be recycled and used for various M-making products, making effective use of steelmaking dust. It is also useful.

[Brief explanation of drawings]

Fig. j111 is a partially cutaway overall perspective view showing one embodiment of the device of the present invention, Fig. 2 is a partially cutaway perspective view of the cylindrical body in the device of the present invention, and Fig. 3 is a perspective view of another example of the cylindrical body. Perspective view, t!
Figure g4 is a diagram showing an example of a free sheet when dust separation is carried out using the apparatus of the present invention, and Figure 5 is a diagram showing an example of a seal sheet around the dust separation apparatus. 1φ0・Duct 200. Chamber 30° top bottom 4. ,, @Body 50, Magnet 6o, Post 7 @@0 Framework 8000 Manual handle 9...
・Rotation p-ler 100. Angle 11°°glft
1112...Gefu board 13” hopper 14- Dust packet 15
°Outlet 16°・Culm 17.18.19
．． 20°・0 dust F...Arc furnace FTo combustion tower M...Magnetic separation device B...Blower-MA-Working remagnetization agent Patent attorney Tsutomu Adachi

Claims (1)

[Claims] 1. In an apparatus that separates magnetic dust and non-magnetic dust by passing exhaust gas from a steelmaking furnace containing a magnetic material through an exhaust gas passage system that generates a magnetic field gradient, a magnetic field gradient forming material is provided. A magnetically permeable cylindrical body with a removably inserted CR on the inside is placed in the exhaust gas passage system, or a magnetically permeable cylindrical body with a magnetic field gradient forming material removably provided on the outside is installed in the exhaust gas passage system. The magnetic dust in the exhaust gas is adsorbed on the outer surface or inner surface of these cylinders, and the magnetic field gradient forming material is separated from the cylinders, thereby releasing the magnetic field. A dust separator configured to collect dust from an inner surface. 2. The dust separation device according to claim 1, wherein the material of the magnetically permeable cylinder is a flexible material. 5 The am of the patent claim in which the magnetic field gradient forming material consists of magnet blocks stacked with the yoke in the dark and the magnetic poles as an anti-blue magnetic field.
m. The dust separation device according to item 1.