JPH05263118A - Device for charging raw material into cylindrical furnace - Google Patents

Abstract

PURPOSE:To smoothly charge raw material from an upper furnace hole without tilting a cylindrical furnace during continuous operation of the cylindrical furnace. CONSTITUTION:This charging device of raw material into a cylindrical furnace is provided with a closing chamber 6 faced to an opening part 4A arranged to an exhaust-gas-hood vertical part above the cylindrical furnace, a raw material back 11 incorporated in the closed chamber, a pushing device 12 for pushing out the raw material in the raw material back by advancing/retreating this raw material back in the direction of the exhaust gas hood opening hole part in the closed chamber, a raw material receiving door 7 for opening/closing between the closing chamber and the outside at raw material charging side and a raw material charging door 9 for opening/closing an interval with the exhaust gas hood opening hole part. By this method, the continuous operation in the cylindrical furnace can be executed, and by rising the packing ratio of the raw material in the furnace, thermal efficiency is improved and the productivity can be risen.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for charging raw materials such as scrap, iron ore, coke and the like into a converter or a cylindrical furnace similar to the above through an upper opening thereof.
Especially at the furnace mouth level without tilting the furnace body during continuous operation,
Furthermore, the present invention relates to a raw material charging device capable of smoothly charging the lower part of the exhaust gas hood above the furnace opening.

[0002]

2. Description of the Related Art In a furnace for charging raw materials from an upper opening such as a steelmaking converter, it is usual to tilt the furnace body to charge the raw materials. This is because the auxiliary equipment such as the exhaust gas hood will be an obstacle if the charging is performed while standing upright.

FIG. 7 is a schematic sectional view for explaining charging of raw materials into a conventional converter. The raw material is stored in a boat-shaped container (called a raw material bag) 41 with one end open at a predetermined place,
The raw material bag 41 is hung by a crane as shown in the drawing, conveyed to the vicinity of the opening 46 of the tilted converter 45, the suspending tool 42 is operated and tilted, and the raw material therein is dropped into the furnace and charged. To do. At the top of the furnace is a hood 4 that collects exhaust gas when the furnace is operating.
3, water-cooled skirt that can be moved up and down at its lower end 4
3a and hood 44 for collecting dust when charging raw materials (dust collecting hood in front of furnace), chain 44 suspended from the lower end in a comb shape
a. In order to smoothly charge the raw material while avoiding interference with these auxiliary equipment, it is necessary to incline the converter 45 at a tilt angle of 50 ° or more. For this reason, the filling rate of the raw material in the furnace, which is represented by the ratio of the total of the apparent volumes of the respective raw material packed beds charged in the furnace to the furnace volume, becomes extremely low.

At present, most of pig iron is produced by a blast furnace. In this blast furnace pig iron method, sinter ore is used as an iron source and high-grade coke is used as a fuel (reducing material). There are restrictions on the available raw fuel. Further, the blast furnace in recent years has become enormous, and since it is not possible to easily stop and restart it once it has been fired, it lacks flexibility in responding to changes in demand for steel products.

In order to solve the above-mentioned problems of the conventional blast furnace ironmaking method, the present applicant uses a cylindrical furnace similar to a converter for steelmaking, and uses a new product using ore and scrap as an iron source. A pig iron method was proposed (see, for example, Japanese Patent Laid-Open No. 1-290711). FIG. 6 is a schematic cross-sectional view showing a furnace used in this ironmaking method and a state of charging the raw materials thereof. As shown in the figure, this tubular furnace 31 has an opening 32 for discharging the gas inside the furnace and charging the raw material in the upper part of the furnace, a primary tuyere 33 for injecting fuel into the lower part of the furnace wall and supporting fuel, if necessary, The upper furnace wall is provided with a secondary tuyere 34 for injecting a combustion-supporting gas, and a discharge port 37 for discharging hot metal and slag at the furnace bottom.

In order to produce hot metal using the cylindrical furnace 31, first, a coke packed bed 35 is provided in the lower part of the furnace, and scrap 36-1, iron ore 36-2, and auxiliary materials such as slag forming agent are provided thereon. To form the filling layer 36. Then, a combustion supporting gas and fuel as necessary are blown into the lower coke packed layer 35 from the primary tuyere 33 to cause a reaction of the following equation (1), and the reaction heat keeps the coke packed layer 35 at a high temperature.

C + 1 / 2O ₂ → CO + 29,400 kcal / kmol C (1) The CO generated in the above formula (1) is blown from the secondary tuyere 34 in the packed layer 36 of scrap and iron ore. Flammable gas and below
The reaction of formula (2) (secondary combustion) occurs. The heat of reaction is used for heating and melting scrap 36-1 and iron ore 36-2.

CO + 1 / 2O ₂ → CO ₂ +67,590 kcal / kmol CO (2) The iron ore (molten iron oxide) melted by this reaction is dropped into the coke packed bed 35 at the bottom to form high temperature coke. It reacts according to the following formula (3) and is immediately reduced.

Fe ₂ O ₃ + 3C → 2Fe + 3CO −108,090 kcal / kmol · Fe ₂ O ₃ (3) Since CO ₂ does not exist in the vicinity of the reaction of the above formula (3),
CO ₂ does not interfere with the reaction of formula (3). And
The CO generated by the equations (1) and (2) is secondarily combusted in the packed bed 36 of scrap and iron ore, so that it is effectively used for heating and melting them and high fuel efficiency is achieved.

As described above, according to the above-mentioned method for producing molten pig iron proposed by the applicant of the present invention, it is possible to continuously produce molten pig iron from scrap and iron ore in a converter-type tubular furnace with good thermal efficiency. However, in the actual operation, it is important to increase the filling rate of the raw material in the tubular furnace in order to improve the thermal efficiency and improve the productivity. However, even in the case of such a furnace, it is necessary to install an exhaust gas hood, a dust collecting hood and the like as shown in FIG. However, there is a great limitation in increasing the filling rate of the raw material in the furnace and improving the thermal efficiency and the productivity.

Therefore, as a charging device capable of minimizing the tilting of the furnace body, the applicant of the present invention moves the extruding plate from one end to the other end of the container along the inner circumference of the gutter-shaped container to extrude the raw material. An apparatus (Japanese Patent Application No. 3-272633), a tilting stand for tilting the raw material back, and a charging chute for advancing and retracting between the tilting stand and the upper opening of the furnace. Wishhei 3
-286481) was proposed.

According to the charging method described above, the raw material can be smoothly charged without tilting or tilting the furnace body, and the filling rate of the raw material in the furnace can be increased. However, in such a device, it is necessary to provide an extruding plate drive device and a roller device for each gutter-shaped container, and an increase in device cost and repair cost cannot be avoided. In the case of this apparatus, tilting of the furnace body is unavoidable, but there is a limit to the improvement of the filling rate of the raw material in the furnace. In addition, since the raw material charging for one time is carried out by fixing the tip position of the gutter-shaped container or the charging chute in both the and the devices, the raw materials are filled in piles in the furnace and the raw material is charged in an average layer thickness. difficult.

[0013]

SUMMARY OF THE INVENTION It is an object of the present invention to smoothly charge a raw material to a level higher than a throat level without tilting the furnace at the start of operation of a cylindrical furnace or during continuous operation. To provide a raw material charging device which can be uniformly carried out and therefore can increase the raw material filling rate in the furnace, and further can load the raw material to a level above the furnace mouth and preheat it if necessary. Especially.

[0014]

The gist of the present invention resides in the following raw material charging device.

The closed chamber facing the opening provided in the vertical portion of the exhaust gas hood above the cylindrical furnace, the raw material bag accommodated in the closed chamber, and the raw material bag in the closed chamber in the direction of the exhaust gas hood opening. And a pushing device that pushes out the raw material in the raw material bag, and the closed chamber is a raw material receiving door that opens and closes and seals between the raw material charging side atmosphere and the exhaust gas hood opening portion. A raw material charging device for a cylindrical furnace, comprising a raw material charging door that opens, closes, and closes.

FIG. 1 is a vertical sectional view showing an embodiment of the raw material charging apparatus of the present invention installed in a cylindrical furnace.
Is a diagram for explaining the details of the raw material charging device of the present invention,
2 is a side view showing a partial vertical section, and FIG. 3 is a plan view showing a partial horizontal section.

As shown in FIG. 1, an exhaust gas hood 4 is provided above a cylindrical furnace 1 to collect reaction product gas in the furnace as exhaust gas through a furnace opening 2 and a water-cooled skirt portion 3 which can be vertically moved up and down. Is provided. An exhaust gas hood opening 4A is provided in the vertical portion of the exhaust gas hood 4, and the raw material charging device of the present invention is installed facing it.

The raw material charging device roughly includes a closed chamber 6, a raw material bag 11, and a pushing device 12. Hereinafter, these details will be sequentially described.

[Closed Chamber] The closed chamber 6 is provided on the work floor 5. As shown in FIG. 3, the closed chamber 6 is composed of a rectangular parallelepiped raw material back chamber 6A and a raw material feeding door drawing chamber 6B provided on one side surface thereof. A raw material receiving door 7 equipped with a moving device 8 as shown in FIGS. 1 and 2 is provided between the closed chamber 6 and the raw material charging side atmosphere, and between the closed chamber 6 and the exhaust gas hood opening 4A. Raw material input door 9 equipped with transfer device 10
Is provided.

There is a raw material receiving opening 6C on the upper surface of the raw material back chamber 6A, and the door sealing packing 7 is in contact with the upper surface.
A raw material receiving door 7 having A is provided. The raw material receiving door 7 can be opened and closed horizontally by a raw material receiving door moving device 8 including, for example, a traveling rail 8A, a traveling trolley 8B and a suspension frame 8C. Suspension stand 8C and raw material receiving door 7
It is desirable to interpose a door pressing cylinder 8D between the above and so that the door can be pressed downward when the door is closed so that the door can be sealed.

At the opening of the raw material back chamber 6A opening to the exhaust gas hood opening 4A, there is a raw material feeding door 9. The raw material feeding door 9 is, for example, a traveling rail 10A, a traveling trolley 10
As shown in FIG. 3, it can be opened and closed by a raw material feeding door moving device 10 composed of B and a drive pulley and a driven pulley on which a wire rope or a chain (not shown) is hung. Further, a door pressing cylinder 9B is provided on the outer edge portion, and a door sealing packing 9A is provided on the inner surface of the raw material back chamber 6A with which the outer edge surface of the raw material feeding door 9 is in contact, so that the door can be pushed and sealed when closed. Is desirable.

[Raw material bag] A trough-shaped raw material bag 11 for receiving and feeding raw material is provided on a roller 6E supported by a roller bearing 6F provided on the surface of the work floor 5 at the bottom of the raw material back chamber 6A. Or put it on the rail through the wheels.

[Pushing Device] The pushing device 12 is
There is a pusher 12A inside the raw material bag 11, which is driven from one end to the other end (from right to left in FIG. 2) along the inner circumference of the raw material bag 11 by a drive device 12D installed outside the raw material bag chamber 6A. Move, extrude and charge raw materials.

The cylinder shaft passing through the raw material back chamber 6A is sealed by a shaft seal member 12C.

The pusher 12A is provided with a back moving cylinder 12B extending in the width direction of the raw material bag, and its rods are provided on both side surfaces of the raw material bag 11 with holes 11 formed therein.
The pusher 12A and the raw material bag 11 are fixed by being inserted into A or the hole 11B, and the raw material feeding bag 11 itself can be moved forward and backward by driving the pusher driving device 12D so that they are interlocked. ..

When the raw material is extruded, the tip position of the raw material bag 11 is worked with the back side stopper 11D at the bottom end which is attached so that the locus of the raw material falling from the tip position is the optimum position of the cylindrical furnace. It can be adjusted using a work floor side stopper 5A provided on the floor 5. Raw material bag 11
Is fixed by the stoppers 11D and 5A and the rod of the back moving cylinder 12B is pulled out from the hole 11A, only the pusher 12A can move to push out the raw material. Further, a bag fixing cylinder 6D is provided on the side surface of the raw material back chamber 6 on the side where the raw material feeding door drawing chamber 6B is not provided, and the rod is inserted into the hole 11C provided on the side surface of the raw material feeding bag 11 so that the stopper can be removed. The raw material feeding bag 11 can be fixed at a position where it cannot be used, and only the pusher 12A can be moved forward to push out the raw material.

In this apparatus, as shown in FIGS. 1 and 3, the raw material bag 11, the pushing device 12 and the like are horizontally installed, but the raw material does not slip down in the raw material bag 11 when receiving the raw material. It may be installed with an inclination so that the pusher output when extruding the raw material becomes small.

[0028]

The operation of charging raw materials such as coke, scrap, ore and the like into a converter-type tubular furnace using the raw material charging apparatus of the present invention having the above-described structure will be described.

First, when the raw material is charged into the raw material bag 11 installed inside the closed chamber 6 provided at the upper part of the exhaust gas hood 4, the raw material feeding door 9 is closed in advance to keep airtightness. After confirming that, the raw material receiving door moving device 8 is used to open the raw material receiving door 7.

Then, the raw material conveyed in an appropriate container is loaded into the raw material bag 11. The raw material bag 11 may be used to carry the raw material, and the raw material bag 11 may be installed in the closed chamber 6 as it is.

When the raw material receiving into the raw material bag 11 is completed, the raw material receiving door 7 is closed and the inside is purged with N ₂ gas or the like, and then the raw material feeding door 9 is opened by using the raw material feeding door moving device 10 to open the raw material. The back 11 is pushed toward the exhaust gas hood opening 4A by the pusher drive device 12D.

FIG. 4 is a cross-sectional view for explaining a method of charging all the raw materials in one extrusion using the apparatus of the present invention.
In addition, in FIG. 4 and FIG. 5 described later, the skirt portion 3 shown in FIG. 1 is omitted.

As described above, the rod of the back moving cylinder 12B attached to the pusher 12A is inserted into the hole 11A of the raw material bag, and the pusher 12A is inserted into the raw material feeding bag 11.
Fixed to. When the pusher 12A is pushed out by the pusher driving device 12D, the roller 6E provided on the work floor 5 has a small resistance and the raw material feeding bag 11 is also pushed out in conjunction therewith. As shown in FIG. 4, the locus T of dropping of the raw material falling from the tip of the raw material feeding bag 11 passes through the optimum position of the furnace, for example, P ₀ point at the center of the furnace opening 2 in the case where the entire amount is extruded once. At the tip end position, the working floor side stopper 5A hits the back side stopper 11D provided to stop the extrusion of the raw material bag 11, and the forward movement of the raw material feeding bag 11 is stopped.

Next, the pusher 12A and the back are fixed (hole
11A and the cylinder 12B for moving the bag are removed), only the pusher 12A moves forward along the inner circumference of the material bag 11, and the material received inside is pushed out to form a cylindrical furnace 1.
It is thrown in. When the feeding is completed, the pusher 12A is retracted, and when it comes to the rear end of the raw material bag 11, before the raw material bag 11 is fed, the raw material bag 11 and the pusher are fixedly interlocked with the back moving cylinder 12B and the hole 11A. And then the raw material feeding door 9 is closed.

In this charging method, since the raw material is charged without tilting the furnace body as shown in the figure, the raw material charging level L can be increased beyond the furnace port 2 to the inside of the exhaust gas hood 4. Is. Therefore, not only the filling rate of the raw material in the furnace can be increased, but also the excess raw material can be piled up to the lower region of the exhaust gas hood and preheated with the exhaust gas.

FIG. 5 is a cross-sectional view for explaining a method in which half of each raw material is charged by two-time extrusion using the apparatus of the present invention. FIG. 5 (a) shows a state where the first extrusion is completed, and FIG. )
The figure shows the state where the second extrusion is completed.

As shown in FIG. 5 (a), in the method of charging in two steps, the mounting position of the back side stopper 11D is set back from that of FIG. 4, and the trajectory T of the raw material falling from the tip of the raw material bag 11 is dropped. Is, for example, P _{1 in} the approximate center of the radius of the furnace
The tip of the raw material bag 11 is advanced to a position that passes through the point. Then, at that position, only the pusher 12A is pushed to the middle portion of the bag to inject half of the raw material, and at that position, the rod of the back moving cylinder 12B is inserted into the hole 11B shown in FIG. 2 to fix the raw material bag and the pusher. .. Next, the raw material bag 11 is retracted in association with the backward movement of the pusher 12A.

As shown in FIG. 5 (b), the tip end of the raw material bag 11 is moved to a position where the falling trajectory T of the raw material falling from the front end of the raw material bag 11 passes through, for example, P _{2 at the} center of the radius of the furnace opening. Retreat. At the loading position, since the back side stopper 11D cannot be used, the rod of the bag fixing cylinder 6D is inserted into the hole 11C to fix the raw material bag 11. Next, remove the pusher and back (fixation between hole 11B and back moving cylinder 12B) and pusher 12
A is extruded and the remaining half of the raw material is put into the cylindrical furnace 1.
Next, the back fixing cylinder 6D and the hole 11C are unfixed. Subsequent operations are the same as in the case of extruding the whole amount once.

In the method of charging in two times as described above, the tip position of the raw material bag 11 can be freely changed as shown in the figure, so that the pile-up phenomenon occurring at the raw material falling position is alleviated and the raw material bag 11 is evenly distributed in the furnace. Raw materials can be charged. Further, the raw material charging level L becomes even flatter than in the case of the above-mentioned single extrusion.

[0040]

The raw material charging apparatus of the present invention can be attached by modifying a part of the existing exhaust gas duct. By using this apparatus, the raw material can be charged without tilting the furnace and with the exhaust gas system sealed, so that it is not necessary to interrupt the continuous operation of the furnace. Further, it becomes possible to charge the raw material up to the furnace mouth level or higher, and it is possible to effectively utilize the sensible heat of the exhaust gas for preheating the raw material to improve the thermal efficiency and the productivity.

Since this apparatus charges the raw material by the pusher method, it is not necessary to tilt the raw material bag largely, so that the space of the closed chamber does not need to be so large. Therefore, when producing hot metal from scrap and iron ore using the existing converter, raw material charging can be carried out without major modification of the existing equipment, and the conventional converter operation can be easily restored. be able to.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing an embodiment of a raw material charging apparatus of the present invention installed in a tubular furnace.

FIG. 2 is a side view showing a partial vertical section for explaining the details of an embodiment of the raw material charging device of the present invention.

3 is a plan view showing a partial horizontal section of FIG. 2. FIG.

FIG. 4 is a cross-sectional view for explaining a method of using the apparatus of the present invention to charge all the raw materials in one extrusion.

5A and 5B are cross-sectional views for explaining a method of charging half of raw materials by two extrusions using the apparatus of the present invention, FIG. 5A is a state in which the first extrusion is completed, and FIG. It is a figure which shows the state which the extrusion of the 1st time was completed.

FIG. 6 is a schematic cross-sectional view showing a cylindrical furnace used in an ironmaking process using ore and scrap as iron sources and a raw material charging state thereof.

FIG. 7 is a schematic cross-sectional view illustrating charging of a raw material into a conventional converter.

[Explanation of symbols]

1: Cylindrical furnace, 2: Furnace mouth, 3: Skirt part,
4: Exhaust gas hood 5: Working floor, 6: Closed room, 7: Raw material receiving door,
8: Raw material receiving door moving device 9: Raw material feeding door, 10: Raw material feeding door moving device, 11: Raw material bag 12: Pushing device

Claims (1)

[Claims] 1. A closed chamber facing an opening provided in a vertical portion of an exhaust gas hood above a tubular furnace, a raw material bag accommodated in the closed chamber, and the raw material bag in the closed chamber, the exhaust gas hood opening portion. And a pushing device that pushes out the raw material in the raw material bag, and the closed chamber has a raw material receiving door that opens and closes and seals between the raw material charging side atmosphere and an exhaust gas hood opening. A raw material charging device for a tubular furnace, comprising: a raw material charging door that opens and closes and seals the space.