JP6344008B2 - Pressure equalization method for top hopper - Google Patents

Description

  The present invention relates to a pressure equalizing method for a top hopper that adjusts the pressure in the top hopper of a blast furnace top charging device that charges raw fuel such as sintered ore and coke into the blast furnace.

As is well known, when charging raw fuel such as sintered ore and coke into a blast furnace, a blast furnace top charging device disposed at the top of the blast furnace is used. As this blast furnace top charging device, for example, as shown in Patent Documents 1 and 2, a bell type blast furnace top charging device provided with a bell hopper, or a bellless equipped with a swivel chute as shown in Patent Document 3 A blast furnace top charging device of the type is provided.
In the bell-type blast furnace top charging apparatus described above, the raw fuel charged in the bell hopper is charged so as to fall into the blast furnace furnace.
On the other hand, in the above-mentioned bell-less blast furnace top charging device, when charging the raw fuel into the blast furnace, productivity of pig iron production, consumption of the blast furnace wall, and generation of deposits on the furnace wall In consideration of suppression and the like, the distribution of the charge at the radial position in the furnace is controlled by the operation of the turning chute from the viewpoint of ventilation.

By the way, since the inside of the blast furnace is, for example, about 294 kPa (3 kgf / cm ² ) in gauge pressure, which is higher than the atmospheric pressure, the blast furnace is operated even when the raw fuel is charged from the top of the blast furnace. It cannot be opened to the atmosphere. Therefore, the above-mentioned blast furnace top charging apparatus includes a furnace top hopper connected to the blast furnace top so that it can be freely opened and closed, and the inside of the blast furnace top and the top hopper is closed. After filling the raw fuel and increasing the pressure in the furnace top hopper, the space between the blast furnace furnace and the top hopper is opened, and the raw fuel is charged into the blast furnace furnace.

  Here, the blast furnace top charging apparatus of Patent Document 1 includes an upper bell hopper and a lower bell hopper, and the upper bell hopper is the above-described furnace top hopper, and is provided for cleaning blast furnace exhaust gas. The clean gas obtained from the ring slit washer is introduced into the upper bell hopper, and then the inert gas is introduced into the upper bell hopper so that the pressure in the upper bell hopper is the same as the pressure in the blast furnace furnace. The raw fuel is charged into the blast furnace. That is, in Patent Document 1, an inert gas is introduced into the upper bell hopper even when the raw fuel is charged into the blast furnace.

Since the clean gas obtained from the ring slit washer provided for cleaning the blast furnace exhaust gas is lower than the pressure in the blast furnace furnace due to pressure loss, in Patent Document 1, a high-pressure inert gas is used. By using it, the pressure in the upper bell hopper can be increased to the pressure in the blast furnace.
However, in the blast furnace top charging device of Patent Document 1, after raising the inside of the upper bell hopper to the same pressure as in the blast furnace, it is not possible even when charging the raw fuel to maintain this pressure. Since the active gas is introduced, there is a problem that the amount of the inert gas used is large and the operation cost of the blast furnace is significantly increased.

Therefore, Patent Document 2 proposes a method of reducing the amount of inert gas used by stopping the introduction of the inert gas when charging the raw fuel from the furnace top hopper.
Further, in Patent Document 3, the blast furnace exhaust gas is introduced into the furnace top hopper instead of the inert gas while the raw fuel is charged into the blast furnace furnace in a state where the furnace top hopper and the blast furnace are in communication with each other. Thus, it has been proposed to reduce the amount of inert gas used.

JP 58-025409 Japanese Patent Laid-Open No. 06-179904 Japanese Patent Laid-Open No. 06-271914

By the way, as in Patent Document 2, when the introduction of the inert gas is stopped when the raw fuel is charged, the pressure difference between the blast furnace and the top hopper becomes large, and the charging of the raw fuel is stabilized. There was a risk that it could not be implemented. In particular, in a bell-less blast furnace top charging device equipped with a swirl chute, the swirl chute cannot accurately control the distribution of charges in the radial position in the furnace, resulting in insufficient ventilation and blast furnace There was a risk that the operation would become unstable.
Moreover, the blast furnace exhaust gas used in Patent Document 3 has a high temperature and contains a lot of dust. For this reason, there has been a problem that the piping to be introduced into the furnace top hopper is likely to deteriorate due to heat and wear.
Furthermore, recently, since the flow rate of raw fuel charged into the blast furnace has increased to, for example, 0.8 m ³ / s or more, the pressure in the top hopper should be controlled with good responsiveness corresponding to this flow rate. Is required. In this case, since it is necessary to increase the gas introduction speed into the furnace top hopper, it is necessary to increase the pipe diameter of the gas introduction pipe.

  The present invention has been made in view of the above-mentioned situation, and uses an inert gas when adjusting the pressure in the furnace hopper of the blast furnace top charging apparatus for charging raw fuel into the blast furnace. The pressure at the top of the furnace hopper can control the pressure inside the furnace top hopper with good responsiveness even when the raw fuel charge flow rate is fast, while reducing the amount of piping and the like. It aims to provide a method.

In order to solve the above-mentioned problem, the pressure equalizing method for the top hopper according to the present invention is a method of adjusting the pressure in the top hopper of the blast furnace top charging device for charging raw fuel into the blast furnace. A primary pressure equalizing step of introducing a clean gas in a gas cleaning device provided in a blast furnace exhaust gas pipe into the furnace top hopper, and an inert gas having a pressure higher than the pressure in the blast furnace. When the raw fuel is charged by introducing into the furnace top hopper and increasing the pressure in the furnace top hopper, and further connecting the inside of the furnace of the blast furnace and the furnace top hopper. And a tertiary pressure equalizing step for adjusting the pressure in the furnace top hopper by introducing the clean gas in the gas cleaning device into the furnace top hopper, the secondary pressure equalizing step and the tertiary The pressure difference between the furnace top hopper and the blast furnace in the pressure equalization process is 30 It is characterized in that there is a Pa or less.

  According to the pressure equalizing method for the furnace hopper with this configuration, the primary pressure equalizing step for introducing the clean gas in the gas cleaning device provided in the blast furnace exhaust gas pipe into the furnace hopper, and the pressure in the blast furnace A secondary pressure equalizing step for introducing a high-pressure inert gas into the furnace top hopper and increasing the pressure in the furnace top hopper. Therefore, after the secondary pressure equalizing step, the inside of the blast furnace and the top hopper , The gas in the blast furnace can be prevented from flowing into the furnace top hopper. Therefore, it is possible to suppress the furnace top hopper from being thermally deteriorated by the high temperature blast furnace gas.

  And a third pressure equalizing step for introducing clean gas in the gas purifier into the furnace top hopper when the raw fuel is charged by communicating the inside of the blast furnace and the top hopper. Therefore, the amount of inert gas used can be significantly reduced. At this time, the pressure of the clean gas in the gas purifier is slightly lower than the pressure in the blast furnace due to the pressure loss of the gas purifier etc., but in the situation where the raw fuel is falling, Gas does not flow back into the furnace top hopper, and the raw fuel can be charged stably.

  Furthermore, in the tertiary pressure equalization process, since the clean gas in the gas purifier using blast furnace exhaust gas is used, the temperature of the gas introduced into the furnace top hopper is low and the dust content is reduced. It is possible to reduce the load due to heat and friction to the pipe, and to suppress deterioration of the piping. In addition, since a sufficient amount of gas is ensured, the pressure in the furnace hopper can be responsive even when the charging speed of the raw fuel is high by increasing the pipe diameter of the gas introduction pipe of the furnace hopper. It becomes possible to control well.

In addition, since the pressure difference between the furnace top hopper and the blast furnace in the secondary pressure equalizing step and the tertiary pressure equalizing step is 30 kPa or less, the inside of the blast furnace and the top of the furnace after the secondary pressure equalizing step are set. When the raw fuel is charged through communication with the hopper, the gas in the blast furnace furnace can be reliably prevented from flowing back into the top hopper, and the raw fuel can be charged stably. Can do.

Moreover, in the pressure equalizing method of the furnace top hopper of this invention, it is preferable that the temperature of the said clean gas used in the said 3rd pressure equalization process shall be 80 degrees C or less.
In this case, since the temperature of the clean gas used in the tertiary pressure equalization step is relatively low, 80 ° C. or less, the heat load on the gas introduction pipe of the furnace top hopper can be reliably reduced. Deterioration of piping can be suppressed.

In the pressure equalizing method for the top hopper of the present invention, it is preferable that the clean gas used in the tertiary pressure equalizing step has a dust content of 0.05 g / Nm ³ or less.
In this case, since the dust content of the clean gas used in the tertiary pressure equalization step is 0.05 g / Nm ³ or less, it is ensured that the gas introduction pipe of the furnace top hopper is deteriorated by friction. Can be suppressed.

  As described above, according to the present invention, when adjusting the pressure in the top hopper of the blast furnace top charging device for charging the raw fuel into the blast furnace, the amount of inert gas used can be reduced and the piping can be reduced. It is possible to provide a pressure equalizing method for the top hopper that can control the pressure in the top hopper with good responsiveness even when the raw fuel charging flow rate is high. It becomes possible.

It is explanatory drawing which showed an example of the blast furnace top charging apparatus to which the pressure equalizing method of the furnace top hopper which is embodiment of this invention is applied. It is explanatory drawing which shows an example of the dust catcher and gas purification apparatus which process blast furnace exhaust gas in this embodiment. It is a flowchart which shows the charging procedure of the raw fuel using a blast furnace top charging apparatus. It is a graph which shows the change of the pressure in the furnace top hopper of a prior art example. It is a graph which shows the change of the pressure in the furnace top hopper of the example of the present invention.

Below, the pressure equalizing method of the furnace top hopper which is one Embodiment of this invention is demonstrated with reference to attached drawing. In addition, this invention is not limited to the following embodiment.
The pressure equalizing method for the top hopper according to this embodiment relates to a method for adjusting the pressure in the top hopper 11 provided in the blast furnace top charging apparatus 10 for charging raw fuel into the blast furnace 1 furnace. is there. FIG. 1 shows an example of a blast furnace top charging apparatus 10 to which the furnace hopper pressure equalization method according to this embodiment is applied.

  As shown in FIG. 1, the blast furnace top charging apparatus 10 is arranged at the top of the blast furnace 1, and includes a plurality of top hoppers 11, 11 arranged in parallel, and the plurality of top hoppers 11, 11. 11, a connecting hopper 12 provided at the lower part of the blast furnace 11, a turning chute 13 inserted into the blast furnace 1 from the lower part of the connecting hopper 12 and turning around the vertical axis in the blast furnace 1, and an inert gas in the furnace hopper 11. Inert gas introduction means 20 for introducing the gas, clean gas introduction means 30 for introducing the clean gas in the gas cleaning device 5 provided in the blast furnace exhaust gas pipe 3 to the furnace top hopper 11, the furnace top hopper 11 and the blast furnace exhaust gas pipe 3 and the exhaust pressure pipe 18 connecting the rear stage side of the gas purifier 5.

A seal valve 15 is provided between the furnace top hopper 11 and the connection hopper 12, and the furnace top hopper 11 and the connection hopper 12 of the plurality of furnace top hoppers 11, 11 arranged in parallel are selectively used. And the other top hopper 11 and the connecting hopper 12 can be shut off. The furnace hopper 11 is provided with a weighing meter 41 and a pressure gauge 42 for detecting the pressure in the furnace top hopper 11.
Further, a gate valve 16 is provided between the connecting hopper 12 and the turning chute 13 so that the inside of the furnace of the blast furnace 1 and the connecting hopper 12 can be shut off. Note that a vibration sensor 43 is disposed in the connecting hopper 12.

  The inert gas introduction means 20 includes an inert gas introduction pipe 21 connected to the inert gas generation facility 9 and an opening / closing valve 22 provided in the inert gas introduction pipe 21. In this embodiment, nitrogen gas is used as the inert gas. The inert gas generation facility 9 is an oxygen plant, and uses nitrogen gas obtained as a by-product in the oxygen plant.

  The clean gas introduction means 30 includes a clean gas introduction pipe 31 connected to the gas cleaning device 5, a clean gas receiving part 32 for temporarily storing clean gas, and between the clean gas receiving part 32 and the furnace top hopper 11. And an on-off valve 33 provided.

  Here, as shown in FIGS. 1 and 2, the blast furnace exhaust gas pipe 3 is provided with a dust catcher 4 for removing coarse dust and a rear stage of the dust catcher 4, and removes dust from the exhaust gas in a wet manner. A gas cleaning device 5 and a furnace top pressure recovery power generation device 7 disposed downstream of the gas cleaning device 5 are provided. A branch pipe branched in the dust catcher 4 is provided with a dry dust collector 6 for removing dust in a dry manner.

As shown in FIG. 2, the gas cleaning device 5 includes a primary venturi scrubber 5a and a secondary venturi scrubber 5b arranged in series. In these primary venturi scrubbers 5a and secondary venturi scrubbers 5b, water is injected to the blast furnace exhaust gas that has passed through the dust catcher 4, thereby reducing the temperature of the blast furnace exhaust gas and removing dust in the blast furnace exhaust gas. Yes.
In the present embodiment, the clean gas introduction pipe 31 is connected to a region after the water is injected in the primary venturi scrubber 5a in the gas cleaning device 5 (a region indicated by a thick line in FIG. 2).

In the present embodiment, as shown in FIG. 1, the exhaust pressure pipe 18 is connected to the rear stage side of the furnace top pressure recovery power generator 7 in the blast furnace exhaust gas pipe 3.
Further, in the present embodiment, a furnace top thermometer 44 and a furnace top pressure gauge 45 are disposed on the blast furnace 1 side portion of the blast furnace exhaust gas pipe 3.

The procedure for charging the raw fuel in the blast furnace top charging apparatus 10 configured as described above and the pressure equalizing method for the top hopper 11 according to the present embodiment will be described with reference to the flowchart of FIG. .
First, in the state where the seal valve 15 of one furnace top hopper 11 is closed, the raw fuel is filled into the furnace top hopper 11 (raw fuel filling step S01). At this time, the raw fuel to be charged is weighed by a weighing meter 41 arranged in the furnace top hopper 11. In the raw fuel filling step S01, the furnace top hopper 11 is open to the atmosphere, and the pressure in the furnace top hopper 11 is atmospheric pressure.

  When the filling of the raw fuel is completed, the furnace top hopper 11 is sealed, and the clean gas introduction means 30 introduces clean gas into the furnace top hopper 11 to increase the pressure in the furnace top hopper 11 (primary pressure equalization step). S02). Here, since the introduced clean gas is obtained by treating the blast furnace exhaust gas with the gas cleaning device 5, it is lower than the pressure in the furnace of the blast furnace 1 due to pressure loss. Therefore, in the primary pressure equalizing step S02, the pressure in the furnace top hopper 11 is lower than the pressure in the furnace of the blast furnace 1.

  Next, the inert gas introduction means 20 introduces an inert gas (nitrogen gas in the present embodiment) into the furnace top hopper 11 to further increase the pressure in the furnace top hopper 11 (secondary pressure equalization step). S03). Here, since the pressure of the inert gas (nitrogen gas) obtained from the inert gas generation facility 9 (oxygen plant) is higher than the pressure in the furnace of the blast furnace 1, the pressure in the furnace top hopper 11. Can be made the same as the pressure in the furnace of the blast furnace 1.

Then, after the secondary pressure equalizing step S03 is completed, the seal valve 15 is opened and the raw fuel is charged into the blast furnace 1 through the connecting hopper 12 (raw fuel charging step S04). In the present embodiment, the raw fuel charging flow rate is set to 0.8 m ³ / s or more.
At this time, the clean gas is introduced into the furnace top hopper 11 by the clean gas introduction means 30, and the pressure in the furnace top hopper 11 is adjusted (third pressure equalization step S05). That is, while the seal valve 15 is opened and the raw fuel is charged, the clean gas is introduced into the furnace top hopper 11.
Here, as described above, the introduced clean gas is lower than the pressure in the furnace of the blast furnace 1 due to pressure loss, and is lower than the pressure in the furnace top hopper 11 in the secondary pressure equalizing step S03. Become. In the present embodiment , the pressure difference between the furnace top hopper and the blast furnace in the secondary pressure equalizing step S03 and the tertiary pressure equalizing step S05 is 30 kPa or less.
The clean gas used in the third pressure equalization step S05 has a temperature of 80 ° C. or lower and a dust content of 0.05 g / Nm ³ or lower.

  Then, the charging state of the raw fuel is grasped by the weigh scale 41 provided in the furnace top hopper 11 and the vibration sensor 43 provided in the connection hopper 12, and the end of the charging is detected. When the charging of the raw fuel is completed, the seal valve 15 is closed, the blast furnace 1 and the top hopper 11 are shut off, and the raw fuel is filled into the top hopper 11 again. This will be repeated. In addition, in this embodiment, since the several furnace top hoppers 11 and 11 are provided, when the seal valve 15 of one furnace top hopper 11 is open | released, the seal valve 15 of the other furnace top hopper 11 is opened. And the raw fuel is sequentially charged from the plurality of furnace top hoppers 11 and 11. In this manner, the raw fuel is charged into the furnace of the blast furnace 1.

  According to the pressure equalization method for the furnace top hopper 11 according to the present embodiment configured as described above, the clean gas in the gas cleaning device 5 provided in the blast furnace exhaust gas pipe 3 is introduced into the furnace top hopper 11. A primary pressure equalizing step S02 and a secondary pressure equalizing step S03 in which an inert gas higher than the pressure in the furnace of the blast furnace 1 is introduced into the furnace top hopper 11 by the inert gas introduction means 20. When the seal valve 15 is opened after the secondary pressure equalizing step S03 and the blast furnace 1 furnace and the furnace top hopper 11 are communicated with each other, the gas in the blast furnace 1 furnace can be prevented from flowing into the furnace top hopper 11. The raw fuel can be charged stably.

  Further, when performing the raw fuel charging step S04 in which the raw fuel is charged by opening the seal valve 15 so that the furnace top hopper 11 and the blast furnace 1 communicate with each other, the clean gas is introduced into the furnace by the clean gas introduction means 30. Since the tertiary pressure equalizing step S05 introduced into the top hopper 11 is provided, the amount of inert gas used can be greatly reduced. At this time, the pressure of the introduced clean gas is slightly lower than the pressure in the blast furnace 1 due to the pressure loss of the gas purifier 5 or the like, but in the situation where the raw fuel is falling, Gas does not flow into the furnace top hopper 11, and the raw fuel can be charged stably.

Further, in the tertiary pressure equalizing step S05, since the clean gas in the gas cleaning device 5 is used, the temperature of the gas introduced into the furnace top hopper 11 is low and the dust content is reduced, and the clean gas introduction pipe It is possible to reduce the load due to heat and friction on the gas pipe 31, and to suppress the deterioration of the clean gas introduction pipe 31. Specifically, the clean gas introduction pipe 31 is connected to a location after the water is injected in the primary venturi scrubber 5a in the gas cleaning device 5, and the clean gas used in the tertiary pressure equalizing step S05. Since the temperature is set to 80 ° C. or less and the dust content of the clean gas is set to 0.05 g / Nm ³ or less, the load on the clean gas introduction pipe 31 due to heat and friction can be surely reduced, Maintenance work of the gas introduction pipe 31 can be reduced.

  In addition, since the clean gas in the gas cleaning device 5 provided in the blast furnace exhaust gas pipe 3 is used, a sufficient amount of gas is secured. Therefore, by increasing the pipe diameter of the clean gas introduction pipe 31, the raw fuel Even when the charging flow rate is high, the pressure in the furnace top hopper 11 can be controlled with good responsiveness.

Furthermore, in this embodiment , since the pressure difference between the furnace top hopper and the blast furnace in the secondary pressure equalizing step S03 and the tertiary pressure equalizing step S05 is 30 kPa or less, the sealing is performed after the secondary pressure equalizing step S03. When opening the valve 15 and charging the raw fuel, it is possible to reliably suppress the gas in the blast furnace 1 from flowing into the furnace top hopper 11. Therefore, the raw fuel can be charged stably.
Moreover, in this embodiment, since the blast furnace top charging apparatus 10 provided with the turning chute 13 is used, by adjusting the pressure in the furnace top hopper 11 as described above, The distribution of charges in the radial position can be controlled with high accuracy, and the blast furnace 1 can be operated stably.

The furnace top hopper pressure equalizing method according to the embodiment of the present invention has been specifically described above, but the present invention is not limited to this, and can be appropriately changed without departing from the technical idea of the present invention. It is.
For example, in this embodiment, although it demonstrated as what adjusts the pressure in the furnace top hopper with which the blast furnace top charging apparatus shown in FIG. 1 was equipped, it is not limited to this, The blast furnace of another structure You may apply to the furnace top hopper of a furnace top charging apparatus.

  In the present embodiment, the inert gas used in the secondary pressure equalization process is described as being nitrogen gas that is a by-product of the oxygen plant. However, the present invention is not limited to this, and other inert gases are used. An active gas may be used. Note that the pressure of the inert gas used in the secondary pressure equalization step needs to be higher than the pressure in the blast furnace.

  Furthermore, in this embodiment, as shown in FIG. 2, although demonstrated as what was provided with the gas purification apparatus provided with the primary venturi scrubber and the secondary venturi scrubber arranged in series, it is limited to this. Alternatively, the cleaning gas may be introduced from a gas cleaning device having another structure.

In the following, experimental results of the confirmation experiments that were conducted to confirm the effects of the present invention will be described.
Using the blast furnace top charging apparatus shown in the above-described embodiment, raw fuel was charged into a blast furnace having a capacity of 5000 m ³ , and the blast furnace was operated at a feed ratio of 2.30.

In the conventional example, as shown in FIG. 4, as the primary pressure equalization process, the clean gas in the gas cleaning device is introduced into the furnace top hopper, and the pressure in the furnace top hopper is 268 kPa (2.7 kgf / cm ² ). It was.
As a secondary pressure equalization step, nitrogen gas having a pressure of 314 kPa (3.2 kgf / cm ² ) is introduced into the furnace top hopper, and the pressure inside the furnace top hopper is 294 kPa (3.0 kgf / cm ² ), the same as in the blast furnace furnace. I made it.
When the raw fuel is charged, nitrogen gas having a pressure of 314 kPa (3.2 kgf / cm ² ) is introduced into the furnace top hopper as a third pressure equalizing step, and the pressure in the furnace top hopper is 294 kPa (3. 0 kgf / cm ² ).

In the example of the present invention, as shown in FIG. 5, as the primary pressure equalization step, the clean gas in the gas cleaning device is introduced into the furnace top hopper, and the pressure in the furnace top hopper is set to 268 kPa (2.7 kgf / cm ^2). ).
As a secondary pressure equalization step, nitrogen gas having a pressure of 314 kPa (3.2 kgf / cm ² ) is introduced into the furnace top hopper, and the pressure inside the furnace top hopper is 294 kPa (3.0 kgf / cm ² ), the same as in the blast furnace furnace. I made it.
When the raw fuel is charged, the clean gas in the gas purifier is introduced into the furnace top hopper as a tertiary pressure equalizing step, and the pressure in the furnace top hopper is set to 268 kPa (2.7 kgf / cm ² ). It controlled so that it might become.

  Here, Table 1 shows the pressure, gas temperature, and dust content of the blast furnace exhaust gas and the clean gas in the gas purifier shown in the embodiment. Note that the dust content of the gas was calculated from the weight change of the filter through which the gas was sampled by inserting a Pitot tube (for example, pollution prevention technology and regulations (fourth edition atmospheric version)). (Refer to the measurement of dust in Chapter 6, Section 5).

In both the inventive example and the conventional example, it was possible to operate the blast furnace without any problem.
Here, in the present invention example, clean gas is used in the third pressure equalization process when the raw fuel is charged, so the amount of nitrogen gas used is reduced by 50000 Nm ³ per day compared to the conventional example. Is confirmed to be possible.

The pressure on the dust catcher inlet side is 294 kPa (3.00 kgf / cm ² ), the gas temperature is 400 ° C. at maximum, the dust content is 10 to 20 g / Nm ^3, and the dust catcher outlet side pressure is 293 kPa (2. 99 kgf / cm ² ), the maximum gas temperature is 200 ° C., the dust content is ³ to 10 g / Nm ³ , the temperature is high, and much dust is contained.
On the other hand, the pressure on the outlet side of the primary venturi scrubber is 283 kPa (2.89 kgf / cm ² ), the gas temperature is 60 ° C. or less, and the dust content is 0.05 g / Nm ³ or less. Is 264 kPa (2.69 kgf / cm ² ), the gas temperature is 40 ° C. or less, the dust content is 0.005 g / Nm ³ or less, the temperature is sufficiently low, and the dust is greatly reduced.
Therefore, it was confirmed that the deterioration of the piping can be suppressed by using a clean gas having a low temperature and a small dust content in the tertiary pressure equalizing step.

1 Blast Furnace 3 Blast Furnace Exhaust Pipe 5 Gas Cleaner 10 Blast Furnace Top Charger 11 Furnace Top Hopper 20 Inert Gas Introducing Means 30 Clean Gas Introducing Means

Claims (3)

A furnace top hopper pressure equalizing method for adjusting a pressure in a furnace top hopper of a blast furnace top charging apparatus for charging raw fuel into a blast furnace,
A primary pressure equalizing step for introducing clean gas in a gas purifier provided in a blast furnace exhaust gas pipe into the furnace top hopper;
A secondary pressure equalization step of introducing an inert gas having a pressure higher than the pressure in the blast furnace into the furnace top hopper to increase the pressure in the furnace top hopper;
Furthermore, when the raw fuel is charged by communicating the furnace of the blast furnace and the furnace top hopper, the clean gas in the gas purifier is introduced into the furnace top hopper to introduce the raw fuel in the furnace top hopper. A third pressure equalizing step for adjusting the pressure;
Equipped with a,
A pressure equalizing method for a furnace top hopper, wherein a pressure difference between the furnace top hopper and the blast furnace in the secondary pressure equalizing step and the tertiary pressure equalizing step is 30 kPa or less . 2. The furnace top hopper pressure equalizing method according to claim 1, wherein the clean gas used in the third pressure equalizing step has a temperature of 80 ° C. or lower. 3. The furnace top hopper leveling unit according to claim 1 , wherein the clean gas used in the third leveling step has a dust content of 0.05 g / Nm ³ or less. Pressure method.

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