JPH07188717A - Method for controlling tapping velocity of iron and slag of blast furnace - Google Patents

Abstract

PURPOSE:To adjust a flowing passage cross sectional area by contraction flow of molten iron and to control the flowing velocity of the molten iron and slag by mounting a communicating tube by connecting with a tapping hole at the outside of a furnace and applying magnetic energy to the molten iron flowing in the communicating tube to give the magnetic pressure. CONSTITUTION:The communicating tube 10 connected with the iron tapping hole 1 arranged at the furnace bottom 9 on the outside of the furnace is mounted and plural electromagnetic energy supplying bodies 11 are arranged in the longitudinal direction of the outer periphery of the communicating tube and surrounds the tube 10. At the time of tapping the molten iron 4 and the molten slag 5 stagnated in the furnace bottom 9 through the tapping hole 1 and flowing in the flowing passage 12 in the communicating tube 10, the electromagnetic energy is applied from the electromagnetic energy supplying bodies 11. By this method, the molten iron 4 is gathered to the center part of the passage 12 by receiving the magnetic pressure, and the molten slag 5 is forcedly pushed to the inner surface of the flowing passage 12, and the molten iron 4 and the molten slag 5 are separated to two liquid flows. The molten slag 5 is solidified and stuck to the inner wall surface of the flowing passage 12 to form the solidified layer by cooling in the cooling passage arranged in the communicating tube 10. By this method, the constant flowing passage diameter is kept and the flowing velocity of the tapped iron and slag can be kept constant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling the speed of molten pig iron discharged from a tap hole of a blast furnace.

[0002]

2. Description of the Related Art As shown in FIG. 6, molten pig iron 4 and molten slag 5 are accumulated in the bottom 9 of a blast furnace. However, since the molten pig iron 4 has a larger specific gravity than the molten slag 5, the molten slag 5 is separated on the molten pig iron 4. It is in the state of doing. When the hot metal 4 and the molten metal 5 were accumulated in the bottom 9 of the blast furnace, the hot metal 4 and the molten metal 5 in the furnace were discharged from the hot metal 1 to the hot metal gutter 8 by opening the hot metal tap 1 .

That is, when tapping the taphole 1 provided in the bottom 9 of the blast furnace to tap the taphole, as shown in FIG.
Of the drilling machine 2 is moved to the front of the blast furnace 2, and the drill 3 (or a gold rod) attached to the drilling machine 2 is driven into the taphole 1 to open the blast furnace bottom 9 as shown in FIG. The hot metal slag work was performed to discharge the accumulated hot metal 4 and slag 5 onto the hot metal gutter 8 through the hot metal hole 1.

When the tap slag from the tap hole 1 is completed, a mud gun 6 is attached to the tap hole 1 as shown in FIG. 9, and the mud 7 in the mud gun 6 is pushed into the tap hole 1 to close it. , The pig iron was stopped. In this way, tap hole 1
The mud 7 filled inside is dried and solidified by heat from the periphery of the tap hole 1. In the next pig iron slag, the solidified mud 7 was opened again by the hole punching machine 2 and the tap slag was repeated.

In the conventional tapping work, the mud 7 filled in the taphole 1 is formed in the taphole 1 immediately after it is opened by a drill 3 (or a gold rod) attached to the boring machine 2. The diameter of the formed hole is determined by the outer diameter of the drill 3 (or the gold rod). In this way, at the early stage of tapping, the tapping is carried out from the tapping hole 1 having a small hole diameter, so that the tapping rate from the tapping hole 1 is as high as that of iron ore in the blast furnace as shown in FIG. Since the speed is lower than the speed at which slag is produced by the reduction melting, the molten iron 4 and the slag 5 both rise in the molten metal surface at the bottom 9 of the blast furnace.

However, as the tapping process progresses, the mud 7 forming the tapping hole 1 is worn away by the tapping slag, so that the diameter (area) of the tapping hole 1 gradually increases and at the same time the tapping hole 1 Since the pressure loss passing through the inside also decreases, the flow velocity of the tap slag gradually increases. Therefore, in the course of tapping slag, the tapping slag speed overtakes the pig iron slag speed, and the molten metal levels of the molten pig iron 4 and molten slag 5 in the blast furnace bottom 9 are lowered.

When the tapping speed in the taphole 1 is thus increased, the wear rate of the mud 7 forming the taphole 1 is also increased, as shown in FIG. 11, and the tapping speed is It increases at an accelerating rate. The level of molten metal 4 and molten metal 5 accumulated in the bottom 9 of the blast furnace decreases due to the increase in the amount of molten iron, and the molten metal 5
When the level of the upper surface of the furnace approaches the level of the inner side of the taphole 1 in the furnace, the gas in the furnace is scattered from the taphole 1 to the front of the furnace, which makes it difficult to continue the tapping slag.

At this stage, the mud gun 6 fills the taphole 1 with the mud 7 to close the taphole 1 and finish the taphole, while the other taphole 1 '(see FIG. 6). Using a hole punching machine, the tapping slag is continued from the tapping hole 1 '. In this way, when the tap slag from the tap hole 1'is completed, the tap slag from the tap hole 1 is started again, and the tap slag is alternately discharged from the pair of tap holes 1 and 1 '. I was going.

[0009]

SUMMARY OF THE INVENTION The above-mentioned prior art work on pig iron slag had the following problems. (1) Pre-furnace work associated with tap slag includes tap hole opening work, plugging work, tap sluice, molten slag repair work, and preparatory work by repeated tap slag. large. It is desirable to reduce these operations, but due to the wear of the mud, the tap time from one tap hole is only 2 to 4 hours, and two tap holes are used alternately, so the front worker Two groups are required, which hinders labor saving. (2) The hot metal pretreatment equipment and the slag treatment equipment for slag treatment in the cast floor require sufficient equipment capacity to handle the maximum values of hot metal and slag at the end of tapping, which is higher than the average capacity. Remarkably large equipment capacity is required. (3) As a means for adjusting the tapping speed, there is no adjusting means other than changing the diameter of the drill and the gold rod when opening the tapping hole. Therefore, the tapping speed is a mud that forms the tapping hole. The rate of tapping waste is determined by the amount of wear. For this reason, when the tapping speed is too low, the operation becomes unstable due to an abnormal rise in the level of the molten metal in the furnace, and when the tapping speed is too high, troubles occur due to insufficient processing capacity in the hot metal pretreatment and slag treatment. (4) 5 to 10% in tapping work using a hole puncher and mud gun, no matter how much the hole puncher and mud gun are mechanized.
2) Poor opening of holes and poor drying of mud occur, resulting in unsteady work, which makes it more difficult to perform labor saving work before the furnace. (5) Since the hot metal slag operation is a batch operation using two tap holes, there is a large change in hot metal quality such as hot metal temperature and hot metal components, and hot metal pretreatment, etc. performed between the hot metal production department and the steelmaking department. Work will be hindered.

The present invention has been made in view of the above-mentioned circumstances, and it is possible to greatly extend the time for tapping from the taphole and to keep the tapping speed as constant as possible. It is an object of the present invention to provide a method for controlling the tapping speed of slag in a blast furnace, which can be controlled at a high speed.

[0011]

The present invention according to claim 1 for achieving the above object is a method for controlling the speed of molten pig iron discharged from a tap hole of a blast furnace, wherein the tap hole is Connected to the outside of the furnace, and equipped with a conducting tube, the electromagnetic energy supply body arranged on the outer periphery of this conducting tube applies magnetic energy to the hot metal flowing in the conducting tube to give a magnetic pressure by electromagnetic repulsion, A method for controlling the tapping speed of slag in a blast furnace, which is characterized in that the cross-sectional area of the flow path is adjusted by contracting flow.

According to a second aspect of the present invention, the tapping speed and the tapping speed are controlled by controlling the amount of electromagnetic energy supplied from the electromagnetic energy supplier to adjust the cross-sectional area of the hot metal flowing in the conductor. The method for controlling the tapping speed of slag in a blast furnace according to claim 1, wherein According to the third aspect of the present invention, by cooling the conducting tube, a solidified layer of molten slag is attached to the inner surface side of the conducting tube to perform cell lining, and the amount of heat removed by cooling is adjusted to reduce the thickness of the solidified layer. The method for controlling tapping slag of a blast furnace according to claim 1, wherein the flow rates of the molten pig iron and the molten slag are controlled by changing the flow rates.

According to the present invention of claim 4, the tapping speed is measured by a flow velocity measuring device provided in the tap gutter of the casting floor or the weight measuring device of a toped car, and the tapping velocity is measured by a flow velocity measuring device provided in the tap gutter. The blast furnace according to claim 2 or 3, characterized in that the measured tapping speed and slag speed are controlled to the target tapping speed and slag speed by feeding back the measured tapping speed and slag speed to the electromagnetic energy supplier. This is a pig iron slag speed control method.

[0014]

According to the present invention, a conducting tube is attached to the outer side of the tap hole, and a magnetic energy is applied to the hot metal flowing in the conducting tube by means of an electromagnetic energy supply body arranged on the outer periphery of the conducting tube, so that the magnetic field generated by electromagnetic repulsion is applied. Since the discharge speed of the molten pig iron is controlled by applying atmospheric pressure and adjusting the cross-sectional area of the flow path by the contraction flow of the molten pig iron, it is possible to freely control the tapping metal velocity without being affected by the mud wear of the taphole. Will be possible.

[0015]

EXAMPLES The structure and operation of the present invention will be described in detail below with reference to examples. In the present invention, as shown in FIG. 1, a conduit tube is connected to the outside of the tap hole 1 arranged in the bottom 9 of the blast furnace.
Wear 10. Although the mounting means of the conduit tube 10 is not specified, for example, a mechanical means similar to that of mounting a mud gun may be used so as to be attachable / detachable. A plurality of (four in the drawing) electromagnetic energy supply bodies 11 are arranged on the outer circumference of the conducting tube 10 so as to surround the body portion in the longitudinal direction.

When the molten pig iron 4 and the molten slag 5 accumulated in the bottom 9 of the blast furnace are tapped through the tap hole 1 and flow through the flow passage 12 in the conduit tube 10, the electromagnetic energy is supplied from the electromagnetic energy supplier 11. 2 is applied, the hot metal 4 receives a magnetic pressure 13 due to an electromagnetic reaction, and gathers at the center of the passage 12 formed in the conduit 10 as shown in FIG. As a result, the molten slag 5 is
It is pushed to the inner surface side of 12 and separated into two liquid streams of the hot metal 4 at the center and the slag 5 at the outside thereof. When a cooling medium such as water is made to flow through the cooling passage 14 provided in the conducting pipe 10 for cooling, the molten slag 5 is solidified and adheres to the inner wall surface of the flow passage 12 provided inside the conducting pipe 10, and the solidified layer 15 To form. Since the slag has a low thermal conductivity, the solidification layer 15 serves as a stable heat insulating layer, and serves as cell lining of the conduit 10.

When the solidified layer 15 is formed on the inner surface of the conduit tube 10 by the slag cell flying as described above, it is not worn like the mud 7 in the taphole 1 and therefore has a constant flow path diameter. It is maintained and the tapping speed can be kept constant. As shown in FIG. 5, as the tapping work progresses, the hole diameter of the tapping hole 1 increases due to wear of the mud.
Since the speed of tapping slag is kept constant by the conduit tube 10, the discharge speed of the molten pig iron flowing in the tapping hole 1 becomes small. For this reason, the mud wear rate in the tap hole 1 also gradually decreases, which is in contrast to the conventional case in which mud wear increases at an accelerated rate with the progress of tap slag, and a significant increase in tap time is achieved. To be achieved.

Next, the procedure for controlling the tapping speed and the tapping speed from the tapping hole 1 will be described with reference to FIG. When a cooling medium such as cooling water is made to flow through the cooling passage 14 provided in the conducting pipe 10 to cool the inner wall, the flow rate of the cooling medium is controlled by the control valve 24 to adjust the heat removal from the inner wall. As a result, the layer thickness of the solidified layer 15 that solidifies and adheres to the inner wall surface of the conduit tube 10 is controlled, and the cross-sectional area of the flow path 12 of the conduit tube 10 can be adjusted.

On the other hand, the hot metal 4 in the central portion of the flow path 12 formed in the conducting tube 10 is applied with electromagnetic energy from the electromagnetic energy supply body 11 and receives electric pressure due to electromagnetic repulsion. The intensity of the electromagnetic pressure is adjusted by controlling the supply amount of the electromagnetic energy to control the flow passage cross-sectional area of the hot metal 4. Such a conduit 10
Control of the flow passage cross section of the hot metal 4 by the electromagnetic energy supply body 11 arranged on the outer circumference of the flow passage, and change of the flow cross sectional area of the flow passage 12 by adjusting the thickness of the solidified layer 15 of the slag formed on the inner wall surface by cooling the conduit 10. By this, it becomes possible to independently control the discharge rates of the hot metal 4 and the molten slag 5.

The tapping speed obtained from the hot metal flow velocity measuring device 18 of the hot metal gutter 17 or the weight measuring device 20 of the tope car 19 and the hot metal gutter 21
The slag velocity obtained from the slag flow velocity measuring device (22) is input to the control device (23), and the control device (23) calculates the target tapping speed and the difference between the slag velocity and the target. And the controller based on the difference from the target
When a control signal is output from 23 to the control valve 24 and the control device 16,
The opening of the control valve 24 is controlled to control the flow rate of the cooling medium supplied to the cooling passage provided in the conduit 10.

In this case, instead of controlling the opening degree of the control valve 24, the amount of magnetic energy applied from the electromagnetic energy supplier 11 is controlled, or the flow rate of the cooling medium and the amount of magnetic energy are simultaneously controlled. You can also do it. The thickness of the solidified layer 15 formed on the inner surface of the conduit tube 10 is adjusted by controlling the amount of cooling medium supplied to the cooling passage 14 of the conduit tube 10 and / or the amount of electromagnetic energy supplied to the electromagnetic energy supplier 11. And the conduit
By combining with the flow passage cross-sectional area adjustment of the hot metal 4 existing in the central part of 10, it becomes possible to obtain the desired tapping speed.

As shown in FIG. 5, the diameter (cross-sectional area) of the tap hole 1
However, in the present invention, the tapping speed is kept constant by the conduit tube 10 in the present invention. Therefore, as the hole diameter of the taphole 1 increases, the flow velocity inside the taphole 1 decreases conversely, and the wear rate of the mud forming the taphole 1 gradually decreases. Therefore, in contrast to the conventional method in which mud wear increases at an accelerated rate with the progress of tap slag discharge, which makes the tap slag speed too high, the conduit pipe does not experience accelerated mud wear. A significant extension of the pig iron slag time is achieved by controlling the pig iron slag at a predetermined speed by 10.

[0023]

As described above, according to the present invention, the following effects can be obtained. (1) Since the tapping slag at a constant speed can be achieved by the conduit pipe, the troubles due to the excessive or excessive tapping speed can be solved,
It is possible to reduce the load on the hot metal pretreatment and slag treatment equipment in the casting floor. (2) As the tapping time can be greatly extended, the number of tapping operations can be greatly reduced, so that the work load before the furnace can be significantly reduced and labor saving before the furnace can be achieved. (3) By making the tapping speed constant and prolonging the tapping time, fluctuations in the quality of the hot metal can be significantly reduced, and the refining cost of the hot metal pretreatment in the next step can be reduced. (4) Since the pig iron slag speed that matches the ironmaking slag inside the blast furnace is possible, the pig iron storage and slag level at the furnace bottom become constant, which can contribute to stable operation of the blast furnace.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an apparatus at the bottom of a blast furnace according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a situation in which the hot metal is subjected to a magnetic pressure to reduce its diameter.

FIG. 3 is a cross-sectional view taken along the line AA of FIG.

FIG. 4 is a flowchart showing a control system of the present invention.

FIG. 5 is a diagram showing a transition of a mud wear rate of a taphole, a taphole diameter, and a tap rate according to the present invention.

FIG. 6 is a vertical sectional view of a furnace bottom portion of a blast furnace according to a conventional example.

FIG. 7 is a vertical cross-sectional view showing a hole opening state by a hole punching machine according to a conventional example.

FIG. 8 is a vertical cross-sectional view showing a state of tapping from a taphole according to a conventional example.

FIG. 9 is a cross-sectional view showing a closed state of a tap hole according to a conventional example by a mud gun.

[Fig. 10] Fig. 10 is a diagram showing a transition of a pig iron slag speed and a pig iron slag speed.

FIG. 11 is a diagram showing a relationship between a mud wear rate of a taphole and a flow rate of molten pig iron in the taphole.

[Explanation of symbols]

 1 tapping hole 2 drilling machine 3 drill 4 molten pig 5 molten slag 6 mud gun 7 mud 8 tapping gutter 9 blast furnace bottom 10 conduit tube 11 electromagnetic energy supply body 12 flow path 13 magnetic pressure 14 cooler 15 solidification layer 16 controller 17 Hot metal gutter 18 Hot metal flow velocity measuring device 19 Toped car 20 Weight measuring device 21 Slag gutter 22 Slag flowing velocity measuring device 23 Control device 24 Control valve

Claims (4)

[Claims] 1. A method for controlling the speed of molten pig iron discharged from a tap hole of a blast furnace, which is connected to the outside of the tap hole and is provided with a conduit pipe, and a conduit pipe is attached to the outer periphery of the conduit pipe. The installed electromagnetic energy supply body applies magnetic energy to the hot metal flowing in the conduit to apply magnetic pressure by electromagnetic repulsion, and adjusts the cross-sectional area of the flow path by the contraction of the hot metal. Speed control method. 2. The tapping speed and the tapping speed are controlled by controlling the amount of electromagnetic energy supplied from the electromagnetic energy supplier and adjusting the flow passage cross-sectional area of the hot metal flowing in the conductor. The method for controlling the tapping speed of a blast furnace according to claim 1. 3. By cooling the conducting tube, a solidified layer of molten slag is attached to the inner surface side of the conducting tube for cell flying, and the amount of heat removed by cooling is adjusted to change the thickness of the solidified layer. The method for controlling tapping slag of a blast furnace according to claim 1, wherein the flow rate of the slag and the slag is controlled. 4. A tapping speed is measured by a flow velocity measuring device provided in a tap gutter of a casting floor or a weight measuring device of a toped car, and a tap velocity is measured by a flow velocity measuring device provided in a tap gutter. The method for controlling the tapping speed of the blast furnace according to claim 2 or 3, wherein the target tapping speed and tapping speed are controlled by feeding back the tapping speed and tapping speed to the electromagnetic energy supplier.