KR101769326B1 - Apparatus and method for dust collecting of blast furnace gas - Google Patents

Abstract

According to an embodiment of the present invention, an apparatus for collecting dust of blast furnace gas comprises: a hopper body having a filter member in an internal space to filter dust contained in blast furnace gas; a supply pipe supplying blast furnace gas to the internal space; a purge pipe supplying purge gas to the internal space; an oxygen concentration measuring instrument measuring oxygen (O_2) concentration of gas flowing into the internal space to transmit an oxygen concentration signal; and a control unit controlling a supply amount of the blast furnace gas and the purge gas in accordance with the oxygen concentration signal.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blast furnace gas collecting apparatus,

The present invention relates to a blast furnace gas dust collecting apparatus and a dust collecting method, and more particularly, to a blast furnace gas dust collecting apparatus and a dust collecting method capable of effectively preventing explosion of blast furnace gas.

Typically, molten iron is produced by blowing hot air at about 1200 ° C or higher into iron ores and coke charged into a blast furnace. That is, the molten iron produced by the combustion of the coke and the reduction and melting of the iron ores flows to the lower side of the blast furnace and is discharged to the outside, and the blast furnace gas (BFG) is discharged through the upper part of the blast furnace.

The blast furnace gas discharged from the blast furnace contains a large amount of dust. In general, the dust collecting device and the particulate dust collecting device sequentially pass the dust collecting process. The dust collecting device is a device for collecting granular particles by separating granular particles by gravity dropping method. The particulate dust collecting device is classified into a wet type dust collecting device and a dry type dust collecting device. Recently, .

Korean Patent Publication No. 10-1993-0012601 (published July 20, 1993)

An object of the present invention is to provide a blast furnace gas dust collecting apparatus and dust collecting method which can effectively prevent blast furnace explosion.

Other objects of the present invention will become more apparent from the following detailed description and drawings.

A blast furnace gas dust collector according to an embodiment of the present invention includes a hopper body having a filter member in an inner space to filter dust contained in blast furnace gas; A supply pipe for supplying the blast furnace gas to the inner space; A purge pipe for supplying a purge gas to the internal space; An oxygen concentration meter for measuring an oxygen (O ₂ ) concentration of the gas introduced into the internal space and delivering an oxygen concentration signal; And a control unit for adjusting the supply amount of the blast furnace gas and the supply amount of the purge gas according to the oxygen concentration signal.

Wherein the blast furnace gas dust collecting device comprises: a supply valve disposed on the supply pipe and capable of regulating a supply amount of the blast furnace gas; And a purge valve disposed on the purge pipe and capable of regulating a supply amount of the purge gas, wherein the control unit can control the opening degree of the supply valve and the purge valve in accordance with the oxygen concentration signal.

Wherein the supply pipe comprises: a first supply pipe extending from one side of the supply valve toward the hopper body; And a second supply pipe extending from the other side of the supply valve, wherein the blast furnace gas dust collecting device includes: a branch pipe branched from one side of the second supply pipe and capable of supplying the blast furnace gas into the internal space; And a branch valve disposed on the branch pipe and capable of regulating a supply amount of the blast furnace gas.

The branch pipe may be provided with a diameter smaller than the diameter of the supply pipe.

The blast furnace gas dust collecting apparatus may further include: a vent pipe for communicating the inside space with the outside; And a vent valve disposed on the ventilation pipe, wherein the control unit can control the opening degree of the vent valve in accordance with the oxygen concentration signal.

The control unit may control to open the closed vent valve, close the opened purge valve, and open the closed branch valve when the oxygen concentration is determined to be equal to or less than the predetermined oxygen concentration.

The blast furnace dust collector includes a first pressure gauge for measuring a gas pressure in the inner space and delivering a first pressure signal; And a second pressure gauge for measuring a gas pressure in the second supply pipe and delivering a second pressure signal, wherein the control unit calculates a pressure difference from the first pressure signal and the second pressure signal, The opening degree of the supply valve and the branch valve can be controlled according to the vehicle.

The blast furnace gas dust collecting apparatus may further include: a discharge pipe for providing a moving path through which the blast furnace gas is discharged from the internal space; And a discharge valve capable of regulating the opening degree of the discharge pipe, wherein the control unit opens the open branching valve and opens the closed supply valve when the pressure difference is judged to be equal to or less than a predetermined pressure difference , And can control to open the discharge valve that is closed.

The purge gas may include an inert gas.

A blast furnace gas dust collecting method according to an embodiment of the present invention includes: a purge gas supply starting step of starting supply of purge gas to an inner space of a hopper body provided with a filter member; An oxygen concentration measuring step of measuring an oxygen (O ₂ ) concentration in the internal space; A purge gas supply interruption step of stopping supply of the purge gas when the measured oxygen concentration is equal to or less than a predetermined oxygen concentration; And an overpressure initiating step of starting supply of the blast furnace gas through a branch pipe branched from a supply pipe for supplying blast furnace gas to the inner space and communicating with the inner space.

Wherein the blast furnace dust collecting method comprises: a pressure difference calculating step of calculating a gas pressure difference in the supply pipe and a pressure of the gas in the internal space; Stopping supply of the blast furnace gas to the branch pipe when the calculated pressure difference is equal to or less than a predetermined pressure difference; And a dust collecting start step of starting supply of the blast furnace gas to the internal space through the supply pipe.

Wherein the purge gas supply start step includes a vent pipe closing step of closing the vent pipe communicating with the inside space and the outside, and the purge gas supply stop step may include a vent pipe opening step of opening the vent pipe .

The supply flow rate of the blast furnace gas supplied in the start-up step may be smaller than the supply flow rate of the blast furnace gas supplied in the dust start stage.

The purge gas may include an inert gas.

The blast furnace gas dust collecting apparatus and the dust collecting method according to an embodiment of the present invention effectively reduce the supply amount of the purge gas and effectively suppress the explosion phenomenon caused by the reaction of the blast furnace gas and the inflow air upon re- have.

1 is a view schematically showing an example of a blast furnace gas dust collector.
2 is a schematic view of a blast furnace gas dust collector according to an embodiment of the present invention.
3 is a schematic view illustrating a connection relationship between main components of a blast furnace gas dust collector according to an embodiment of the present invention.
4 is a schematic view showing a flow chart of a blast furnace gas collection method according to an embodiment of the present invention.

The present invention relates to a blast furnace dust collector and a dust collecting method, and embodiments of the present invention will be described below with reference to the accompanying drawings. The embodiments of the present invention can be modified in various forms, and the scope of the present invention should not be construed as being limited to the embodiments described below. The embodiments are provided to explain the present invention to a person having ordinary skill in the art to which the present invention belongs. Accordingly, the shape of each element shown in the figures may be exaggerated to emphasize a clearer description. In addition, the connection referred to below should be construed to include not only the case where two components are directly connected but also the case where they are indirectly connected through another medium.

1 is a view schematically showing an example of a blast furnace gas dust collector.

1, the blast furnace gas collecting apparatus 1 has a hopper body 10 in which a filter member 12 is disposed in an internal space 14 formed therein. The blast furnace gas (BFG) discharged from the blast furnace (not shown) firstly separates the granular particles through a dust collecting device (not shown) and then moves to the blast furnace dust collector 1 The fine particles are subjected to a dust collecting treatment. The blast furnace gas dust collecting apparatus 1 includes a supply pipe 20 extending from the dust collecting device toward the hopper body 10 and providing a path for introducing the blast furnace gas into the internal space 14 and a filter member 12 The supply pipe 20 and the discharge pipe 30 are provided with a discharge pipe 20 and a discharge pipe 30 which are provided in the supply pipe 20 and the discharge pipe 30, The supply valve 22 and the discharge valve 32, which are capable of adjusting the opening degree,

A vent pipe 50 communicating with the outside is disposed on the upper side of the hopper body 10. A vent pipe 50 is disposed on the upper side of the hopper body 10 to regulate the opening of the vent pipe 50, A vent valve 52 for regulating the pressure may be disposed. A rupture plate member 60 may be disposed on the upper side of the hopper body 10 to rupture the rupture of the gas pressure in the inner space 14 to maintain the gas pressure in the inner space 14. [ A purge pipe 40 is provided on the lower side of the hopper body 10 to provide a path through which the purge gas flows into the internal space 14. A purge pipe 40 is provided with a purge pipe 40, A bracket 42 may be disposed. The purge gas is introduced into the inner space 14 to discharge the air introduced into the inner space 14 to the outside. The purge gas may include an inert gas and may include nitrogen (N ₂ ) gas.

There may be a case where the blast furnace gas dust collecting apparatus 1 is restarted after the operation of the blast furnace gas dust collecting apparatus 1 is stopped due to the stop of the blast furnace operation or the repair work of the blast furnace gas dust collecting apparatus 1. [ When the operation of the blast furnace gas dust collector 1 is interrupted, the outside air flows into the inner space 14 and the air introduced into the inner space 14 and the blast furnace There arises a problem that the gas reacts and explodes. Therefore, at the time of restarting the blast furnace gas dust collecting apparatus 1, a purging operation for supplying the purge gas before supplying the blast furnace gas and discharging the air introduced into the inside space 14 to the outside is essential.

The purge operation is started by opening the purge valve 42 with both the supply valve 22 and the discharge valve 32 closed and the purge gas is introduced into the internal space 14 The air is exhausted to the outside along the ventilation pipe 50. The purge gas pressure gauge 44 measures the gas pressure in the internal space 14 and the blast gas pressure gauge 24 measures the pressure of the blast furnace gas in the supply pipe 20. When the gas pressure in the inner space 14 and the pressure of the blast furnace gas in the supply pipe 20 become equal to each other, the purge valve 42 and the vent valve 52 are closed, thereby terminating the purging operation.

There is a risk that the residual air in the internal space 14 is not discharged smoothly to the outside, and the blast gas reacts with the blast gas when the blast furnace gas is supplied again, despite the purge operation of supplying the purge gas. Further, in order to prevent explosion due to abrupt volume expansion of the blast furnace gas, the purge gas must be supplied to the inner space 14 at a pressure equal to the pressure of the blast furnace gas, and a large amount of purge gas is used for the purge operation Problems also exist. SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a blast furnace gas dust collecting apparatus and dust collecting method capable of effectively preventing explosion and reducing the amount of purge gas used when the blast furnace gas is supplied again.

FIG. 2 is a schematic view of a blast furnace gas dust collector according to an embodiment of the present invention, and FIG. 3 is a schematic view showing a connection relationship between main components of a blast furnace gas dust collector according to an embodiment of the present invention.

2, the blast furnace gas collecting apparatus 100 according to an embodiment of the present invention includes a hopper body 110 disposed in an inner space 114 in which a filter member 112 is formed . A supply pipe 120 is provided at one side of the hopper body 110 to provide a path through which the blast furnace gas moves to the inner space 114 and a blast furnace gas is discharged from the inner space 114 at the other side of the hopper body 110 A discharge pipe 130 is provided. The supply valve 122 and the discharge valve 132 may be disposed on the supply pipe 120 and the discharge pipe 130 respectively and the amount of flow of the blast furnace gas may be controlled by the supply valve 122 and the discharge valve 132 .

The supply pipe 120 may be disposed on the lower side of the hopper body 110 to supply the blast furnace gas to the inner space 114 on the lower side of the filter member 112. The discharge pipe 130 is connected to the filter member 112, And may be discharged to the upper side of the hopper body 110 so as to discharge the blast furnace gas from the inner space 114 on the upper side. The supply pipe 120 and the discharge pipe 130 may be disposed at one side and the other side of the hopper body 110 facing each other for smooth movement of the blast furnace gas in the internal space 114. The blast gas introduced into the lower side of the inner space 114 through the supply pipe 120 passes through the filter member 112 and moves to the upper side of the inner space 114 and flows into the inner space 114 through the discharge pipe 130. [ As shown in FIG. A transfer pipe 170 for providing a path for moving the collected dust may be disposed on the lower side of the hopper body 110. A transfer valve 172 capable of adjusting the opening degree of the transfer pipe 170 may be disposed on the transfer pipe 170 . Therefore, the dust collected in the filter member 112 falls to the lower side of the inner space 114, and the dropped dust can be moved along the transfer pipe 170 and stored separately.

The supply pipe 120 includes a first supply pipe 120a extending from one side of the supply valve 122 toward the hopper body 110 and a second supply pipe 120b extending from the other side of the supply valve 122 toward the dust collecting device. (120b). The branch piping 180 is branched from one side of the second supply piping 120b and extends to one side of the hopper body 110 and is connected to the inner space 114 from the second supply piping 120b through the branch piping 180. [ The blast furnace gas may be supplied. The branch piping 180 may extend from one side of the second supply piping 120b and be connected to one side of the first supply piping 120a and may be connected to the second supply piping 120b May be supplied to the inner space 114 along the first supply pipe 120a. A branch valve 182 can be disposed on the branch pipe 180 and the amount of the blast gas movement can be adjusted by the branch valve 182. [ The branch piping 180 is disposed to supply the blast furnace gas to the inner space 114 to fill the gas pressure in the inner space 114. The diameter d ₂ of the branch piping 180 is set to be smaller than the diameter d ₂ of the supply pipe 120 (D ₁ ) of the inner diameter (d ₁ ).

The purge piping 140 may be connected to one side of the hopper body 110 to supply purge gas to the internal space 114. The purge pipe 140 may be connected to one side of the first supply pipe 120a and the purge gas supplied from the purge pipe 140 may be introduced into the inner space 114 through the first supply pipe 120a . A purge valve 142 is disposed on the purge pipe 140, and the purge gas supply amount can be adjusted by the purge valve 142. The purge gas may include an inert gas and may include nitrogen (N ₂ ) gas.

A vent pipe 150 communicating with the outside space may be disposed on the upper side of the hopper body 110. A vent valve 152 is disposed on the vent pipe 150 to open the vent pipe 150. [ Can be adjusted. The ventilation pipe 150 can provide a passage through which the air that has been introduced into the internal space 114 when the purge gas is supplied into the internal space 114 is discharged to the outside, The gas pressure in the space 114 can be adjusted. A rupture plate member 160 capable of adjusting the gas pressure in the inner space 114 by rupturing when the gas pressure in the inner space 114 is abruptly increased can be disposed on the upper side of the hopper body 110.

An oxygen concentration meter 154 is disposed on one side of the hopper body 110 to measure the concentration of oxygen (O ₂ ) contained in the gas in the internal space 114. The oxygen concentration measuring system 154 may measure the oxygen concentration of the gas in the inner space 114 through various methods. Hereinafter, for convenience of explanation, the oxygen concentration refers to the oxygen concentration of the oxygen in the inner space 114 It is defined as being a volume. The oxygen concentration measuring system 154 may be disposed on the vent pipe 150 and may measure the oxygen concentration of the gas exhausted through the vent pipe 150. The oxygen concentration measuring system 154 may measure the concentration of oxygen contained in the gas in the inner space 114 and transmit the oxygen concentration signal T to the control unit 108. [

The first pressure gauge 116 is disposed on one side of the hopper body 110 and can measure the gas pressure in the internal space 114. The second pressure gauge 124 is disposed at one side of the second supply pipe 120b to measure the gas pressure inside the second supply pipe 120b. The first pressure gauge 116 may measure the gas pressure in the interior space 114 to deliver the first pressure signal P ₁ to the control unit 108 and the second pressure gauge 124 may communicate with the second supply pipe 120b ) To deliver the second pressure signal (P ₂ ) to the control unit (108).

3, the control unit 108 is electrically connected to the oxygen concentration meter 154, the first pressure gauge 116 and the second pressure gauge 124, and is connected to the oxygen concentration signal T, The supply valve 122, the discharge valve 132, the purge valve 142, the branch valve 182, the vent valve 152, and the transfer valve 172 (Fig. ₁ ) in accordance with the signal P ₁ and the second pressure signal P ₂ Can be controlled.

A specific operation of the blast furnace gas dust collector 100 according to an embodiment of the present invention will now be described.

The control unit 108 closes the supply valve 122, the discharge valve 132, the purge valve 142 and the branch valve 182 when the blast furnace or the blast furnace gas dust collector 100 is shut down. The control unit 108 closes the vent valve 152 and opens the purge valve 142 so that the purge gas is supplied to the internal space 114. In this case, As the purge gas is supplied, the oxygen concentration measuring system 154 measures the oxygen concentration in the inner space 114 and delivers the oxygen concentration signal T to the control unit 108 in accordance with the measured oxygen concentration. The control unit 108 determines whether the measured oxygen concentration is equal to or less than the predetermined oxygen concentration and opens the vent valve 152 when the oxygen concentration measured by the oxygen concentration measurement system 154 is equal to or less than the predetermined oxygen concentration, The purge valve 142 is closed, thereby stopping the supply of the purge gas into the internal space 114.

It is preferable that the oxygen concentration as a reference for stopping the purge gas supply is 5.6% or less, but it is more preferable to stop the supply of the purge gas when the oxygen concentration is 1% or less. The oxygen concentration of less than 5.6% is the theoretically derived oxygen concentration that can suppress the explosion when the blast furnace gas is supplied. The oxygen concentration of less than 1% is experimentally derived to suppress the explosion occurrence when the blast furnace gas is re- .

The control unit 108 sequentially opens the branch valve 182 after the purge valve 142 is closed or after the purge valve 142 is closed. When the branch valve 182 is opened, the blast furnace gas flows into the inner space through the branch pipe 180, and the gas pressure in the inner space 114 is filled with the blast furnace gas. The branch piping 180 is provided with a diameter d ₂ that is smaller than the diameter d ₁ of the supply piping 120 and the branch piping 180 has a smaller amount of blast furnace 120 than the case where blast furnace gas is supplied by opening the supply valve 122 The gas is introduced into the inner space 114. The blast gas is supplied to the inner space 114 through the branch pipe 180 so that the explosion can be effectively prevented from being generated as a large amount of blast furnace gas flows into the inner space 114, The gas pressure in the inner space 114 can be effectively increased by using the blast furnace gas introduced into the inner space 114 through the furnace. Therefore, the gas pressure in the inner space 114 can be effectively increased by minimizing the use amount of the purge gas as compared with the conventional method of increasing the gas pressure in the inner space 114 by using the purge gas.

The first pressure gauge 116 measures the gas pressure in the inner space 114 and transfers the first pressure signal P ₁ to the control unit 108 while the second pressure gauge 124 measures the gas pressure in the second supply pipe 120b, And delivers the second pressure signal P ₂ to the control unit 108. The second pressure signal P < ₂ > The control unit 108 uses the first pressure signal P ₁ and the second pressure signal P ₂ to calculate the pressure difference between the gas pressure in the inner space 114 and the blast furnace gas pressure in the second supply pipe 120b And closes the branch valve 182 when it is determined that the pressure difference is equal to or less than the preset pressure difference. The difference in pressure between the gas pressure in the inner space 114 and the blast furnace gas pressure in the second supply pipe 120b as a reference for closing the branch valve 182 is preferably ± 50 g / cm ² , more preferably 0 g / cm < ² >. In order to positively suppress the explosion of the blast furnace gas due to the blast gas pressure in the supply pipe 120 and the pressure difference in the inner space 114 when the blast furnace gas supply is started again through the supply pipe 120 to be.

The control unit 108 may sequentially open the supply valve 122 and the discharge valve 132 after closing the branch valve 182 or after closing the branch valve 182 so that the blast furnace gas The dust collecting operation is started. In addition, the control unit 108 may appropriately adjust the opening degree of the transfer valve 172 as the dust collecting operation of the blast furnace proceeds, so that the collected dust is collected through the transfer pipe 170.

4 is a schematic view showing a flow chart of a blast furnace gas collection method according to an embodiment of the present invention.

4, the blast furnace gas collection method according to an embodiment of the present invention includes a purge gas supply start step S100 for opening the purge valve 142 to start the supply of the purge gas to the internal space 114, A purge gas supply interruption step S300 for closing the purge valve 142 when the measured oxygen concentration is equal to or lower than a predetermined oxygen concentration, (S400) for opening the branch valve (182) and supplying the blast furnace gas to the inner space at the same time as the supply of the gas is stopped or after stopping the supply of the purge gas to start the gas pressure in the inner space (114) . The purge gas supply start step S100 may further include an aeration pipe closing step S110 for closing the aeration valve 152. The purge gas supply stopping step S300 may include a ventilation pipe 152 for opening the aeration valve 152, (S310). ≪ / RTI >

Also, in the blast furnace dust collecting method according to an embodiment of the present invention, the gas pressure in the inner space 114 and the gas pressure in the supply pipe 120 are measured after the start of pressurization (S400) (S600) for closing the branch valve (182) when the calculated pressure difference is equal to or less than the predetermined pressure difference to terminate the gas pressure filling in the internal space (114) by the blast furnace gas, And a dust collecting start step (S700) for opening the valve 122 and the discharge valve 132. [

It is preferable that the oxygen concentration serving as a reference for closing the purge valve 142 is 5.6%, which can prevent the blast due to the supply of the blast furnace gas. More preferably, the oxygen concentration serving as a closing reference of the purge valve 142 may be 1%. The pressure difference between the gas pressure in the inner space 114 and the gas pressure in the supply pipe 120 as a reference for closing the branch valve 182 is preferably ± 50 g / cm ² , more preferably 0 g / cm ² Lt; / RTI >

Therefore, the blast furnace gas dust collecting apparatus and the dust collecting method according to an embodiment of the present invention effectively reduce the supply amount of the purge gas and effectively suppress the explosion phenomenon generated by the reaction of the blast furnace gas and the inflow air upon re- can do.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, Therefore, the technical idea and scope of the claims set forth below are not limited to the embodiments.

100: blast furnace dust collector 108: control unit 110: hopper body
112: filter member 114: internal space 116: first pressure gauge
120: supply pipe 120a: first supply pipe 120b: second supply pipe
122: supply valve 124: second pressure gauge 130: exhaust pipe
132: discharge valve 140: purge piping 142: purge valve
150: vent pipe 152: vent valve 154: oxygen concentration meter
160: rupture plate member 170: transfer pipe 172: transfer valve

Claims (14)

A hopper body having a filter member in an inner space and capable of filtering dust contained in the blast furnace gas;
A supply pipe for supplying the blast furnace gas to the inner space;
A supply valve disposed on the supply pipe and capable of regulating a supply amount of the blast furnace gas;
A purge pipe for supplying a purge gas to the internal space;
A purge valve disposed on the purge pipe and capable of regulating a supply amount of the purge gas;
An oxygen concentration meter for measuring an oxygen (O ₂ ) concentration of the gas introduced into the internal space and delivering an oxygen concentration signal; And
And a control unit for adjusting the supply amount of the blast furnace gas and the supply amount of the purge gas according to the oxygen concentration signal,
Wherein the supply pipe comprises: a first supply pipe extending from one side of the supply valve toward the hopper body; And a second supply pipe extending from the other side of the supply valve,
The blast furnace gas dust collecting apparatus
A branch pipe branched from one side of the second supply pipe and capable of supplying the blast furnace gas into the internal space;
A branch valve disposed on the branch pipe and capable of regulating a supply amount of the blast furnace gas;
A first pressure gauge for measuring a gas pressure in the inner space and delivering a first pressure signal; And
And a second pressure gauge for measuring a gas pressure in the second supply pipe and delivering a second pressure signal,
Wherein the control unit controls the opening degree of the supply valve and the purge valve in accordance with the oxygen concentration signal, calculates a pressure difference from the first pressure signal and the second pressure signal, Wherein the opening degree of the supply valve and the branch valve is controllable. delete delete The method according to claim 1,
Wherein the branch pipe is provided with a diameter smaller than the diameter of the supply pipe. The method according to claim 1,
The blast furnace gas dust collecting apparatus
A ventilation pipe communicating with the outside of the internal space; And
Further comprising a vent valve disposed on the ventilation pipe,
Wherein the control unit controls the opening degree of the vent valve in accordance with the oxygen concentration signal. 6. The method of claim 5,
Wherein the control unit controls to open the closed vent valve, close the opened purge valve, and open the closed branch valve when the oxygen concentration is determined to be equal to or less than a predetermined oxygen concentration, Device. delete The method according to claim 1,
The blast furnace gas dust collecting apparatus
A discharge pipe for providing a movement path through which the blast furnace gas is discharged from the internal space; And
Further comprising a discharge valve capable of regulating the opening of the discharge pipe,
Wherein the control unit controls to open the branching valve that has been opened, opens the supply valve that is closed, and opens the discharge valve that is closed when the pressure difference is determined to be equal to or less than a predetermined pressure difference. . The method according to claim 1,
Wherein the purge gas includes an inert gas. A purge gas supply start step of starting supply of the purge gas to the inner space of the hopper body provided with the filter member;
An oxygen concentration measuring step of measuring an oxygen (O ₂ ) concentration in the internal space;
A purge gas supply interruption step of stopping supply of the purge gas when the measured oxygen concentration is equal to or less than a predetermined oxygen concentration; And
A pressurization initiating step of starting supply of the blast furnace gas through a branch pipe branched from a supply pipe for supplying blast furnace gas to the inner space and communicating with the inner space;
A pressure difference calculation step of calculating a gas pressure difference in the supply pipe and a pressure of the gas in the internal space;
Stopping supply of the blast furnace gas to the branch pipe when the calculated pressure difference is equal to or less than a predetermined pressure difference; And
And starting a supply of the blast furnace gas to the internal space through the supply pipe. delete 11. The method of claim 10,
Wherein the purge gas supply start step includes an aeration pipe closing step of closing the aeration pipe communicating with the interior space outside,
Wherein the purge gas supply interruption step includes a vent piping opening step of opening the vent piping. 11. The method of claim 10,
Wherein the supply flow rate of the blast furnace gas supplied in the start-up step is smaller than the supply flow rate of the blast furnace gas supplied in the start of the collection. 11. The method of claim 10,
Wherein the purge gas comprises an inert gas.

Images