JPH03229809A - Device for preventing clogging of iron ore discharging pipe in pre-reduction furnace in smelting reduction equipment - Google Patents

Abstract

PURPOSE:To obtain the subject device, which can smoothly supply sintered iron ore into a smelting reduction furnace without clogging a discharging hole with the sintered iron ore by constituting the device so as to discharge the sintered iron ore developed in the discharging hole of dispersion plates for discharging the pre-reduced iron ore with vertical movement of crushing rod. CONSTITUTION:During executing the pre-reduction to the iron ore in a pre- reduction furnace 2, by continuously or intermittently working an air cylinder 33, the crushing rod 30 passing through a discharging pipe 19 is vertically moved at the fixed pitch together with an outer pipe 31. As the result, the iron ore sintered in the discharging hole 12a of dispersion plates 12, at the opening end thereof and in the discharging pipe 19, is broken through with the crushing rod 30 to prevent the clogging of the discharging pipe 19. Therefore, the pre- reduced iron ore can smoothly be supplied into the smelting reduction furnace 1.

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to a device for preventing blockages occurring in the discharge section of pre-reduced iron ore of a pre-reduction furnace in an iron ore smelting reduction facility. It is.

[Prior Art] Iron ore and carbonaceous material are supplied into a converter-type smelting reduction furnace containing an iron bath, and the iron ore is melted by blowing oxygen into the smelting reduction furnace from above through a lance. Iron ore smelting reduction equipment is known.

FIG. 2 is a schematic explanatory diagram of such melting reduction equipment. As shown in FIG. 2, the smelting reduction equipment includes a converter-type smelting reduction furnace 1 and an area above the smelting reduction furnace 1 for preliminary reduction of iron ore, which is the main raw material supplied into the smelting reduction furnace 1. A fluidized tank type pre-reduction furnace 2 provided in the main material storage tank 3,
It consists of a storage tank 4 for auxiliary raw materials.

The melting reduction furnace 1 includes a converter-type furnace body 5 and a furnace opening 5a of the furnace body 5.
A lance 6 inserted vertically into the furnace body 5 through a lance 6, a stirring waste blowing lower provided on the bottom wall and side wall of the furnace body 5, and a main raw material supplying material provided in a hood 8 covering the furnace mouth 5a. It consists of a chute 9, a chute 10 for supplying auxiliary raw materials, and a gas discharge port 11.

The preliminary reduction furnace 2 includes a distribution disk 12 provided at the lower part of the furnace and having a large number of nozzles 13, a gas blowing chamber 14 formed in the furnace below the distribution disk 12, and a gas blowing chamber 14 formed above the distribution disk 12. A preliminary reduction chamber 15 is formed in the furnace. The gas blowing chamber 14 is provided with a gas blowing port 16, and the preliminary reduction chamber 15 is provided with a raw material supply chute 17 and a gas discharge port 18.

The upper surface of the dispersion plate 12 is formed into a mortar shape, and a discharge pipe 19 for pre-reduced iron ore is attached to a discharge hole 12a in the center thereof.

The discharge pipe 19 extends downward through the bottom wall of the preliminary reduction furnace 2 and is connected to the chute 9 of the smelting reduction furnace 1 via an L-shaped valve 20 and two intermediate storage tanks 21 .

A gas conduit 22 is attached to a gas outlet 11 provided in the foot 8 of the smelting reduction furnace 1 , which leads to a gas injection port 16 provided in the gas injection chamber 14 of the preliminary reduction furnace 2 . A dust collecting cyclone 23 is provided in the middle of the gas conduit 22.

The gas discharge port 18 of the pre-reduction furnace 2 is equipped with a gas pipe 24.
is attached, and a dust collecting cyclone 25 is provided in the middle of the gas exhaust pipe 24.

The main raw material storage tank 3 and the raw material supply chute 17 of the preliminary reduction furnace 2 are connected by a duct 26.
The auxiliary raw material storage tank 4 and the auxiliary raw material supply chute 10 of the melting reduction furnace 1 are connected by a duct 27 .

A predetermined amount of molten iron 28 is stored in the smelting reduction furnace 1, and iron ore of a predetermined particle size as a main raw material that has been prereduced in the pre-reduction furnace 2 is supplied through the chute 9 into the smelting reduction furnace 1. Through the chute 10, carbonaceous materials such as coal as auxiliary raw materials and flux are supplied into the melting reduction furnace 1.

Oxygen gas is blown into the furnace from the furnace mouth 5a of the melting reduction furnace 1 through the lance 6 vertically inserted into the furnace body 5, and then through the gas blowing lower provided on the bottom wall and side wall of the furnace body 5. A stirring gas such as nitrogen gas is blown into the blast ore 28 in the furnace.

The carbon in the carbon material and molten iron 28 supplied into the furnace reacts with the oxygen gas blown through the lance 6 to generate Co gas. It reacts with gas to become CO2 gas. Due to the sensible heat of the Co2 gas generated at this time, the iron ore in the molten iron 28 is melted and reduced by the carbon in the carbonaceous material to become molten pig iron.

On the other hand, high-temperature exhaust gas generated from inside the smelting reduction furnace 1 during refining is discharged from the gas outlet 11 of the hood 8, passes through the gas conduit 22, and is blown into the gas blowing chamber 14 of the preliminary reduction furnace 2. . The high-temperature exhaust gas blown into the gas blowing chamber 14 passes through the nozzle 13 of the distribution plate 12 and blows out into the preliminary reduction chamber 15 , and is supplied from the storage tank 3 through the duct 26 and the chute 17 to the preliminary reduction chamber 15 . Iron ore 29 of a predetermined particle size within is preheated in a fluidized state and prereduced.

The iron ore pre-reduced in this manner is discharged from the pre-reduction furnace 2 through the discharge pipe 19 attached to the discharge hole 12a of the dispersion plate 12, passes through the L-shaped valve 20, and is transferred to the two intermediate storage tanks 21. They are temporarily stored alternately in the two intermediate storage tanks 21 and then cut out alternately from the two intermediate storage tanks 21 and supplied into the melting reduction furnace 1 . Since the iron ore supplied into the smelting reduction furnace 1 has been pre-reduced as described above, the reduction process can be reduced and thermal efficiency can be improved.

[Problems to be Solved by the Invention] In the above-mentioned equipment, the distribution disk 12 provided in the preliminary reduction furnace 2 is made of refractory material. Therefore, heat is stored by the high-temperature exhaust gas ejected into the preliminary reduction chamber 15 through the nozzle 13 of the distribution disk 12.

On the other hand, the iron ore 29 supplied into the preliminary reduction furnace 2 is 8 m
The particle size is adjusted to the following.

For this purpose, when the discharge of the pre-reduced iron ore from the pre-reduction furnace 2 through the discharge pipe 19 is temporarily stopped, the inside of the discharge hole 12a of the distribution plate 12 and its opening end as well as the discharge The iron ore present in the pipe 19 is
The material is heated to a temperature of about 800° C. or higher, becoming semi-molten and sintered.

Due to the iron ore sintered in this way, the discharge hole 12a of the dispersion plate 12 and the discharge pipe 19 are blocked, and the pre-reduced iron ore cannot be discharged from the pre-reduction furnace 2. arise.

Therefore, an object of the present invention is to provide a dispersion plate of a fluidized tank type preliminary reduction furnace in an iron ore smelting reduction facility. To provide a device that can smoothly supply pre-reduced iron ore to a smelting reduction furnace without causing blockage with sintered iron ore in a discharge hole and a discharge pipe for discharging pre-reduced iron ore. It's about doing.

[Means for Solving the Problems] The apparatus of the present invention is capable of reducing iron ore which has been pre-reduced in a pre-reduction furnace having a dispersion disk from which a pre-reduction gas is ejected.
In a discharge pipe for discharging from the reduction furnace, the upper end of which is attached to the discharge hole of the distribution disk, an upper portion of which may protrude from the discharge hole of the distribution disk from below along the axis of the discharge tube. A crushing rod that can move up and down,
and an active mechanism provided at the lower part of the crushing rod for vertically moving the crushing rod, so as to prevent clogging of the discharge pipe by sintered iron ore caused by the vertical movement of the crushing rod. It is characterized by the fact that it is

Next, the apparatus of the present invention will be explained with reference to the drawings. FIG. 1 is a vertical sectional view of the lower part of a pre-reducing furnace equipped with the apparatus of the present invention. As shown in Figure 1, the preliminary reduction furnace 2
A dispersing disk 12 is provided in the lower part thereof, which has a large number of nozzles 13, and in the center thereof has a discharge hole 12a for pre-reduced iron ore. The upper end of a discharge pipe 19 for pre-reduced iron ore, which extends downward through the bottom wall of the pre-reduction furnace 2, is attached to the discharge hole 12a of the dispersion@12.

In the discharge pipe 19, from below, passing through the discharge pipe 19,
A crushing rod 30 whose upper portion can protrude into the preliminary reduction chamber 15 from the discharge hole 12a of the dispersion plate 12 is inserted so as to be movable up and down along the axis of the discharge pipe 19.

An outer tube 31 is provided on the outside of the crushing rod 30 with a predetermined gap therebetween. Outer tube 31 and crushing rod 3
0 are fixed to each other by a flange 32 or the like attached to close the lower end of the outer tube 31, and the space between the upper portion of the outer tube 31 and the crushing rod 30 is open.

An air cylinder 33 is provided at the bottom of the crushing rod 30, and the lower end of the crushing rod 30 is connected to a rod 33a of the air cylinder 33. By the operation of the air cylinder 33, the crushing rod 30 moves up and down together with the outer tube 31, and when the crushing rod 30 rises the most, it protrudes into the reduction chamber 15 from the discharge hole 12a of the dispersion plate 12 as shown by the dotted line. .

A cooling inert gas inlet 34 is provided at the bottom of the outer tube 31 . 35 is an outer pipe 3 on the upper part of the discharge pipe 19.
1. This is a support plate provided between 1 and 1.

[Function] While preliminary reduction of iron ore is being carried out in the preliminary reduction furnace 2, the air cylinder 33 is operated continuously or intermittently, and the crushing rod 3o passing through the discharge pipe 19 is moved at a constant pitch along with the outer tube 31. Move it up and down.

As a result, the iron ore sintered in the discharge hole 12a of the dispersion plate 12, its open end, and the discharge pipe 19 is crushed by the crushing rod 30, thereby preventing the above-mentioned portion from being blocked.

[Example] A stainless steel discharge pipe 19 with an inner diameter of 200 on was attached to the discharge hole 12a of the distribution plate 12 of the preliminary reduction furnace 2 with a height of 10 m and an inner diameter of 1 m. The discharge pipe 19 had a double structure, and a cooling gas was flowed inside to cool it.

A crushing rod 30 made of stainless steel and having a diameter of 40 nvn was inserted into the discharge pipe 19 so as to be movable up and down. The crushing rod 30 was attached so that its upper end was located within the discharge hole 12a of the distribution plate 12, and its lower end protruded from the discharge pipe 19.

On the outside of the crushing rod 30, an outer tube 31 made of stainless steel is provided at a predetermined distance from the crushing rod 3o, and from a gas inlet 34 provided at the lower part of the outer tube 31, the outer tube 31 and the crushing rod are connected. 30
Nitrogen gas was blown into the gap between the outer tube 31 and the crushing rod 30 to cool it.

The blown nitrogen gas was discharged into the preliminary reduction chamber 15 from the upper end opening of the outer tube 31.

While the iron ore was being pre-reduced in the pre-reduction furnace 2, the air cylinder 33 was operated to move the crushing rod 30 up and down together with the outer tube 31.

As a result, the discharge hole 12a of the distribution plate 12, its open end, and the discharge pipe 19 are not clogged with sintered iron ore, and the iron ore pre-reduced in the pre-reduction furnace 2 is discharged. Pass the tube 19 smoothly into the melting reduction furnace 1.
could be supplied within

[Effects of the Invention] As described above, according to the present invention, a device for discharging pre-reduced iron ore, which is provided in the dispersion plate of a fluidized tank type pre-reduction furnace in an iron ore smelting reduction facility, is provided. The discharge hole and the discharge pipe are not clogged with sintered iron ore, and the pre-reduced iron ore can be smoothly supplied to the smelting reduction furnace, which is an industrially useful effect.

[Brief explanation of drawings]

FIG. 1 is a vertical sectional view of the lower part of a preliminary reduction furnace equipped with the apparatus of the present invention, and FIG. 2 is a schematic explanatory diagram of the smelting reduction equipment. In the drawing, ■, smelting reduction furnace, 2... preliminary reduction furnace, 3.4.
... Storage tank, 5. Furnace body, 6. Lance, 7. Gas inlet, 8. Hood,
9, 10... Chute, 1 gas discharge port, 12a... discharge hole, 14... gas blowing chamber, 16... gas blowing port, 18. gas discharge port, 20... L-shaped valve, 22. ...Gas pipe, 24.Gas discharge pipe, 28. Molten iron, 30..Crushing rod, 32..Flange, 34..Gas inlet, I2..Dispersion plate, 13..Nozzle, 15.. Preliminary reduction chamber, 17... Chute, 19... Discharge pipe, 21... Intermediate storage tank, 23.25... Dust collection cyclone, 26.27... Duct, 29... Iron ore, 31...Outer tube, 33...Air cylinder, 35...Support plate.

Claims (1)

[Scope of Claims] 1. The upper end of the dispersion plate is connected to a discharge hole of the dispersion plate for discharging iron ore pre-reduced from the reduction furnace in a pre-reduction furnace having a dispersion plate from which pre-reduction gas is ejected. A crushing rod is provided in the attached discharge pipe so that the crushing rod can be moved vertically from below along the axis of the discharge pipe so that the upper part thereof can protrude from the discharge hole of the distribution plate. and a drive mechanism provided at the lower part of the crushing rod to prevent the discharge pipe from being clogged with sintered iron ore by vertical movement of the crushing rod. A device to prevent clogging of iron ore discharge pipes in preliminary reduction furnaces in smelting reduction equipment. 2. An outer tube is provided on the outside of the crushing rod with a predetermined gap spaced concentrically with the crushing rod, and an inert gas is caused to flow through the gap between the crushing rod and the outer tube to remove the inert gas. 2. The apparatus of claim 1, wherein the crushing rod and the outer tube are cooled by gas.