JPS6113913Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to the improvement of a raw material charging device for a vertical reduction furnace for gas reduction of iron ore, pellets, etc. using reducing gas. The object of the present invention is to provide a raw material device for a vertical reduction furnace that can effectively prevent raw material particle size segregation in the circumferential direction within the vertical reduction furnace that is configured to sufficiently cope with the above problems.

The first material charging device for a vertical reduction furnace is designed to keep the furnace height as low as possible and fully handle high-pressure operations.
A charging device as shown in the figure is provided. That is,
A furnace top hopper 2 receives raw materials from a conveyor 1, and a system that receives raw materials in this hopper 2 via a gate valve 3 and a seal valve 4, and supplies raw materials to a vertical furnace 7 via a gate valve 5 and a seal valve 6. In a vertical reduction furnace 7 equipped with an exhaust pressure tank 8, a partition plate 9 is provided in the upper interior of the reduction furnace to form a storage space for raw materials, and a charging tube 10 in which the raw materials are allowed to flow down into the partition plate 9.
For example, as shown in FIG. 2, which shows a cross-sectional view taken along line A-A in FIG. A storage hopper 12 is configured within the chamber 7, and an exhaust gas outlet pipe is installed in the furnace wall 14 of the space formed between the partition plate 9 and the stock line of the charge 13 whose apex is the lower end of the charging tube 10. This is a raw material charging device provided with 15.

Note that 16 is a hopper for temporarily storing the raw material flowing out from the gate valve 5 of the equalizing pressure tank 8 to prevent dynamic flow due to falling of the raw material and improving grain size segregation in the furnace radial direction within the storage hopper 12. This is a charging cylinder provided in 12.

However, in this charging device, the furnace core 11
A chevron-shaped stock line with the lower end of the charging cylinder 10 as its apex is formed at the lower end of each charging cylinder 10 which is arranged intermittently at equal intervals on a circular locus with a radius D centered at . Since the raw material flowing down is supplied rolling around the lower end of the charging cylinder 10,
There is a tendency that there are many fine grains directly below, and coarse grains increase in the middle part between the charging cylinders 10-10 on the circular locus.

When such particle size segregation occurs in the circumferential direction within the furnace at the radius D from the furnace core 11, the distribution of the reducing gas flow in the circumferential direction becomes non-uniform and the required amount of reducing gas increases.

In order to improve particle size segregation that is formed on a concentric circular locus that connects the lower end openings of multiple charging cylinders arranged at equal intervals on a concentric circular locus centered on the furnace core, a large number of charging tubes are It is possible to install the tubes closely together to reduce rolling of the raw material flowing down from the bottom end of the charging tube in the circumferential direction, but in this case, the area of the exhaust gas passage in the furnace core between adjacent charging tubes is drastically reduced. As a result, the above-mentioned ventilation resistance of the exhaust gas increases, which causes problems such as an increase in the blowing pressure of the reducing gas, and the exhaust gas itself from the furnace core becomes difficult to discharge in a short period of time due to dust attached to the cylinder. arise.

The present invention does not cause the above-mentioned problems, and the charging tubes are formed on a concentric circular locus that connects the lower end openings of a plurality of charging tubes arranged intermittently at equal intervals on a concentric circular locus centered on the furnace core. The purpose of the present invention is to provide a raw material charging device that eliminates grain size segregation (hereinafter referred to as circumferential grain size segregation), and its gist is as follows.

In this invention, a partition plate is provided inside the upper part of the vertical reduction furnace to form a storage space for raw materials, and charging tubes for allowing the raw material to flow down into this partition plate are arranged at equal intervals on a concentric circular locus centered on the furnace core. A storage hopper is formed in the furnace by suspending and fixing a plurality of hoppers. In a raw material charging device for a vertical reduction furnace provided with an exhaust gas outlet pipe, the charging tube has a material passage area that gradually increases downward at least at the bottom of the charging tube, and an arcuate opening is formed at the lower end. A vertical reduction furnace characterized in that a concentric ring-shaped raw material discharge port centered on the furnace core is formed in the furnace below the partition plate by using the above-mentioned group of arc-shaped openings. This is a raw material charging device.

The present invention will be explained below based on an illustrated embodiment.

3, 4, 5, and 6 show examples of the charging tube used in the raw material charging device of the present invention. 16,17
FIGS. 4 and 6 are vertical sectional views taken along the line B-B shown in FIGS. 4 and 6, and FIGS. 4 and 6 are views taken along the line C-C in FIGS. 3 and 5. FIG.

The charging tube 16 shown in FIGS. 3 and 4 has a diameter at the upper end.
It has a circular opening 18 of 2r and has a circular locus of (D+r) and radius (D-r) centered on the furnace core 11 at the lower end,
It has a 1/6 arc-shaped opening 19 formed by both radiation trajectories at an angle π/3 from the furnace core 11, and a raw material passageway from the upper end opening (raw material inlet) 18 to the lower end opening (raw material outlet) 19. The area is gradually increased.

Note that both circumferential ends of the lower end opening may be rounded as shown by broken lines in FIG.

The charging cylinder 17 shown in FIGS. 5 and 6 is constructed by connecting a charging cylinder 16 having a shape as shown in FIGS. 3 and 4 to the lower end of a cylindrical body 22 having an inner diameter of 2r.

In addition, in FIGS. 3 and 5, 20 indicates the charging cylinder 16,
It is a horizontal flange provided at the upper end of 17, and is connected to the partition plate 9 with bolts, nuts, etc., and is connected to the charging tube 16,
17 is suspended and fixed.

The charging cylinder 16 (or 17) as shown in FIGS. 3 and 4 (or FIGS. 5 and 6) is
By replacing the charging tube 10 of the conventional charging device shown in FIGS. , a width on a circular locus of radius D centered on the furnace core 11
A 2r ring-shaped raw material discharge port 21 can be formed.

At that time, as shown in the developed view of FIG. 8 (or FIG. 9), a furnace of sufficient size is placed between the charging tubes 16 (or 17) over the entire height direction of the charging tubes 16 (or 17). A core exhaust gas passage 23 can be formed.

As described above, in the present invention, a ring-shaped raw material discharge port is formed by the group of arc-shaped lower end openings of the charging cylinder, so the raw material discharged from the lower end opening of each charging cylinder flows in the direction of the furnace circumference. The flow only occurs in the radial direction of the furnace, and the raw material particle size segregation (particle size distribution) in the circumferential direction at each position in the radial direction of the furnace can be effectively prevented.

In addition, the present invention uses a charging tube in which the raw material passage area gradually increases from the upper end opening to the lower end opening, so that the exhaust gas from the furnace core is distributed between adjacent charging tubes over the entire height of the charging tube. A passageway has been formed.

As a result, the reduction gas injection pressure does not increase or the exhaust gas from the furnace core becomes difficult to discharge.
The gas flow distribution in the radial direction of the furnace can be maintained uniformly in the circumferential direction, and the required amount of reducing gas can be maintained at a low level.

[Brief explanation of the drawing]

Figures 1 and 2 are explanatory diagrams of a conventional raw material charging device for a vertical reduction furnace, Figure 2 is a sectional view taken along line A-A in Figure 1, and Figures 3 to 9 are illustrations of the raw material charging device of the present invention. An explanatory diagram of the device, Figures 3 and 4 are explanatory diagrams of the charging cylinder used in the present invention, and Figure 7 is an illustration of the charging cylinder used in Figures 3 and 4 or Figures 5 and 6. Figure 1 shows the vertical reduction furnace in the A-A direction, Figures 8 and 9 are shown in Figures 3 and 4.
FIG. 6 is an enlarged developed cross-sectional view of the charging tube when the charging tube shown in FIG. 5 or FIG. 6 is employed. 1 is a conveyor, 2 is a furnace top hopper, 3 is a gate valve, 4 is a seal valve, 5 is a gate valve, 6 is a seal valve, 7 is a vertical reduction furnace, 8 is an equalizing pressure tank, 9 is a partition plate, 10 11 is a furnace core, 12 is a storage hopper, 13 is a charge, 14 is a furnace wall, 15 is an exhaust gas outlet pipe, 16 is a charging cylinder, 17 is a charging cylinder, 18 is an upper end opening, 19 is the lower end opening, 20 is the horizontal flange,
21 is a ring-shaped raw material discharge port, 22 is a cylindrical body, 23
is the furnace core exhaust gas passage.

Claims (1)

[Scope of utility model registration request] A partition plate is installed in the upper interior of the vertical reduction furnace to form a storage space for the raw material, and a plurality of charging tubes for allowing the raw material to flow down the partition plate are arranged at equal intervals on a concentric circular locus centered on the furnace core. A storage hopper is formed in the furnace by fixing the main suspension, and the exhaust gas is led to the furnace wall in the space formed between the partition plate and the charge stock line with the bottom end of the charging cylinder as its apex. In a material charging device for a vertical reduction furnace provided with a tube, the material passage area gradually increases downward at least at the bottom of the charging tube, and an arcuate opening is formed at the lower end of the charging tube. Material charging of a vertical reduction furnace characterized by adopting a cylinder and forming a concentric ring-shaped material discharge port with the furnace core as the center core in the furnace below the partition plate using the group of circular arc-shaped openings. Device.