KR20050023886A - An apparatus for removing dust in exhaust gas - Google Patents

Abstract

PURPOSE: To provide an apparatus for burning exhaust gas exhausted into the atmosphere by a combustion means disposed in front of water sealing valve during blowing down or blowing operation of blast furnace, thereby removing dust contained in the exhaust gas and recovering combustion heat of the exhaust gas. CONSTITUTION: In an apparatus(1) comprising a gas pipe(108) equipped with a water sealing valve(108a) and installed in rear of dust catcher(104) and Bischoff scrubber(106) connected to blast furnace(102), and a gas storage tank(110) connected to the gas pipe to prevent exhaustion of dust contained in an exhaust gas exhausted during blowing down or blowing operation of the blast furnace, the apparatus comprises a gas recovery pipe(10) which is connected to the gas pipe in front of the water sealing valve in such a way that the gas recovery pipe is communicated with the gas pipe, and on which a first cutout valve(12) is installed; a combustion means(30) installed on the gas recovery pipe; and a bypass pipe(50) which is branched off from a part of the gas return pipe in front of the combustion means, and on which a second cutout valve(52) is installed in such a way that the bypass pipe is communicated with the gas recovery pipe.

Description

Dust removal device during blast furnace ventilation work {AN APPARATUS FOR REMOVING DUST IN EXHAUST GAS}

The present invention relates to a device for removing dust in the exhaust gas discharged during shelter and blowing operations performed in the blast furnace, and more specifically, the dust is discharged to the atmosphere by burning and removing the dust in the exhaust gas by the combustion means. The present invention relates to a dust removal apparatus during a blast and blow operation of an improved blast furnace.

In general, a hopper is installed at the upper part of the blast furnace to produce molten iron so that coke and iron ore can be charged into the blast furnace.

That is, as shown in FIG. 1, coke and iron ore are charged into the blast furnace 102 at an appropriate ratio by two hoppers 103 disposed on the blast furnace 102, respectively. Thereafter, the hot air of about 1200 ° C. is supplied to the inside of the blast furnace 102 through the hot air permeable 111 to produce molten iron.

On the other hand, when the production of the molten iron is stopped due to maintenance, inspection and breakdown of the blast furnace 102 and other various causes, the operation of the air blast to discharge all the gas in the blast furnace is performed. After the inspection is completed, in the case of normalizing the blast furnace 102 for the production of molten iron, a blowing operation is performed.

The air-venting operation is a task of discharging the gas into the air by opening a bleeder 116 provided on the upper part of the blast furnace 102 to purge the residual gas in the blast furnace 102, the seating of the charge In order to monitor the condition of the charges until the wind pressure is zero (zero) for the air blowing operation is carried out through the depressing operation to gradually reduce the amount of air supplied into the blast furnace (102).

As shown in FIG. 1, when the wind pressure reaches 600 g / cm 2 to prevent gas backflow in the gas reservoir 110, the water reservoir 112 is opened to supply water to the water sealing valve 108a. The back flow of gas from 110 was prevented.

At this time, since the blasting operation in the blast furnace 102 is continued even during the operation of the air shelter, if the water-sealed side 108a of the blast furnace 102 exited is blocked, the pressure of the blast furnace 102 is increased.

In order to prevent the pressure rise of the blast furnace 102 as above, the water pressure is zero by opening the bleeder 116 immediately before the gas is shut off and the gas is discharged into the atmosphere. (0g / cm 2).

Therefore, there is a problem of polluting the surrounding equipment and the air by the gas poisoning of the operator by the gas discharged through the bleeder 116, the dust contained in the discharged gas, etc. during the above-described air-venting operation.

In order to solve the conventional problems as described above, there is Korea Patent Application No. 2001-0083591 (Invention name: dust scattering prevention device and method by forced pressure discharge during blast blast operation).

However, Republic of Korea Patent Application 2001-0083591 Bleeder at the minimum wind pressure (100g / N㎥) after making the optimum gas blocking condition by the controller while recovering the gas to the gas reservoir by the fan to the maximum before the gas blocking for the air-venting operation It is essential to minimize the release of air to the gas by opening the gas, but this may cause negative pressure in the blast furnace, which may cause explosion, and some residual gas is discharged into the atmosphere through the bleeder. There was a problem.

The present invention is to solve the conventional problems as described above, by removing the dust contained in the gas by burning the gas discharged by the combustion means arranged in the front end of the water-sea sinter, the blast furnace improved to recover the combustion heat The purpose is to provide a dust removal device during the blowing operation.

In order to achieve the above object, the present invention, the gas pipe having a water seal side is installed at the rear end of the gun, the wet vibration damper connected to the blast furnace, and provided with a gas reservoir connected to the gas pipe, the gas discharged during the operation of the blast furnace, blowing An apparatus for preventing the discharge of dust contained in the gas, comprising: a gas recovery pipe connected to the front end of the water sealing side and provided with a first shutoff valve; Combustion means installed in the gas recovery pipe; And a bypass pipe branched from the front end of the combustion means and provided with a second shutoff valve to communicate with the gas recovery pipe. The air blowing operation of the blast furnace, characterized by burning dust contained in the discharged gas. Time dust removal equipment.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Figure 2 is a schematic view of the dust removal apparatus during the blast furnace, blow operation of the blast furnace according to the present invention, Figure 3 is a detailed view of the dust removal apparatus during the blast, blow operation of the blast furnace according to the present invention.

2 and 3 shows the dust removal device (1) during the operation of the blast furnace, the air blower according to the present invention, the structure will be described as follows.

Dust removal device 1 during the blast furnace, blowing operation according to the present invention includes a gas recovery pipe 10, the combustion means 30, and the bypass pipe 50. Same as

As shown in FIG. 2, the blast furnace 102 for producing molten iron is connected to a dry dust generator 104, and a wet dust generator 106 is connected to a rear end of the dry dust generator 104, and the wet dust generator 106 is It is connected to the gas reservoir 110 by the gas pipe 108.

At this time, the gas pipe 108 is formed with a U-shaped water-sealed side 108a, the water-sealed side 108a is provided with a water supply pipe 112 provided with a water supply valve 112a, and a drain valve (not shown). It is configured to selectively block the gas flowing through the gas pipe 108 through the supply and discharge of water to the water sealing (108a).

Meanwhile, as shown in FIG. 3, a gas recovery pipe 10 branched from the front end of the water sealing edge 108a is installed on the gas pipe 108, and an oxygen concentration detector is provided on the gas recovery pipe 10. (44), the exhaust gas amount control valve 46, and the first shut-off valve 12 are provided, and a combustion means 30 including a burner 31 that uses coke oven gas (COG) as a fuel at the rear end thereof. It is installed.

At this time, the combustion means 30 has a structure in which a burner 31 is mounted in a case 33 through which the exhaust gas is supplied from the gas recovery pipe 10, and the case 33 is a discharge means such as a chimney. The exhaust gas, which is connected by the 70 and the pipe 38 and burned by the combustion means 30, is discharged through the discharge means 70.

The case 33 is connected to communicate with the combustion air supply pipe 35, and the combustion air supply pipe 35 has a combustion air fan 37, an air shutoff valve 39, and an air volume control valve 42. It is installed so as to supply the air necessary for ignition of the burner 31 into the case 33.

On the other hand, the heat exchanger 72 is installed on the pipe 38 between the combustion means 30 and the discharge means 70 is configured to recover the heat of the gas burned by the combustion means 30.

In addition, a combustion gas discharge pipe 32 in which the third shutoff valve 34 is installed is formed at an upper end of the case 33 of the combustion means 30 so as to communicate with the pipe 38 in which the heat exchanger 72 is installed. have.

On the other hand, although not shown, the heat exchanger 72 is configured to pass through a heat transfer medium (for example, air or water) and recover heat of the burned gas therein, thereby recovering heat as described above. By supplying to the required process by the heat transfer medium can be used to increase the thermal efficiency.

In addition, a bypass pipe 50 communicating with the gas recovery pipe 10 is connected to a front end of the first shutoff valve 12 installed in the gas recovery pipe 10, and on the bypass pipe 50. The second shutoff valve 52 is provided.

The bypass pipe 50 installed as described above is connected to communicate with the pipe 38 between the discharge means 70 and the heat exchanger 72.

Reference numerals 48 and 49 in FIGS. 2 and 3 denote exhaust gas and combustion air flow rate detectors.

Each valve, detector, fan, etc. of the dust removal device 1 during the operation of the blast furnace, the blower according to the present invention configured as described above is electrically connected to the operation panel 90 having a widely used operation stage Works like this:

As illustrated in FIG. 2, when the operation of the blast furnace 102 is to be stopped for maintenance or inspection of the blast furnace 102, a ventilation operation is performed, and the blast furnace 102 is performed as described above. When the wind pressure in the c) is 900g / cm 2, the operation panel 90 opens the steam valve 102a and the nitrogen valve 102b installed in the blast furnace 102 to allow steam and nitrogen into the blast furnace 102. To be blown.

When the operation is performed as described above, as shown in Figure 3, the operation panel (not shown) closes the second shut-off valve 52 installed in the bypass pipe 50 to the bypass pipe 50 ), The third shutoff valve 34 is opened, and then the air shutoff valve 39 is opened to supply combustion air into the case 33 of the combustion means 30, and the combustion air fan 37 is opened. It works.

Accordingly, air is supplied into the case 33 of the combustion means 30 by the combustion air fan 37, at which time the COG valve of the fuel pipe for supplying COG to the burner 31 of the combustion means 30. The burner 31 is ignited by the ignition device 31b after 31a is opened by the operation panel 90 and the combustion air and COG are supplied.

Subsequently, when it is detected by the pressure detector 113 installed in the blast furnace 102 that the wind pressure of the blast furnace 102 is a reference wind pressure (900g / ㎠) for gas blocking, the operation panel 90 is a water supply valve ( 112a) is opened so that water supply starts at the water sealing edge 108a.

As described above, when gas is blocked by the water sealing edge 108a as water is supplied, the operation panel 90 opens the first shut-off valve 12, and at this time, the exhaust gas containing the dust and the like. Is supplied to the combustion means 30, the dust in the exhaust gas is burned and removed.

On the other hand, the gas amount regulating valve 46 provided at the front end of the gas recovery pipe 10 is adjusted to maintain the water level of the water sealing edge 108a by adjusting its opening degree so that the top pressure does not rise, accordingly the combustion When it is detected that the amount of gas flowing into the means 30 is increased by the exhaust gas flow rate detector 48, the operation panel 90 adjusts the air volume control valve 42 to supply the amount of combustion air to the burner 31. To increase.

Therefore, the amount of combustion air supplied to the combustion means 30 is adjusted according to the inflow amount of the exhaust gas flowing into the combustion means 30 to maintain the combustion conditions in which dust in the exhaust gas is completely burned.

As described above, the exhaust gas which is burned by the burner 31 of the combustion means 30 and the dust is removed is discharged through the pipe 38 communicating with the combustion gas discharge pipe 32 from the combustion means 30. In this case, the heat of the burned gas is recovered and recycled by the heat exchanger 72 installed in the pipe 38.

Thereafter, as the wind pressure decreases over time, the amount of the gas flowing into the combustion means 30 gradually decreases, and the composition of the gas is mainly composed of nitrogen and steam supplied into the blast furnace 102. When the valve 31a is closed, the burner 31 of the combustion means 30 is naturally extinguished.

When the air volume supplied to the combustion means 30 is completely extinguished as described above and the pressure in the blast furnace 102 is equal to the atmospheric pressure, the operation panel 90 controls the gas flow control valve 46 and the first shutoff valve 12. ) And then open the top bleeder 116 to discharge only steam and nitrogen to the top bleeder 116.

That is, the gas in the blast furnace 102 containing the dust during the operation of the air is not discharged into the atmosphere through the top bleeder 116, it is possible to completely block the emission of dust to the atmosphere.

Thereafter, when the maintenance or maintenance work of the blast furnace 102 is completed, the blowing operation to resume the molten iron production is subjected to the following preparation process before implementation.

That is, since only the top bleeder 116 is opened before the blowing operation is performed, the purge valve 104a of the steam valve 102a and the nitrogen valve 102b, the dry damper 104 and the wet damper 106 are purged. The valve 106a is opened to purge all the locations, and the logo 102 is filled with nitrogen and steam.

As shown in FIG. 2, when the purge is completed as described above, the operation panel 90 sequentially closes the top bleeder 116 in a state in which all the purge valves are opened, and is installed in the blast furnace 102. When a pressure increase in the blast furnace 102 is detected by the pressure detector 113, the gas flow control valve 46 and the second shutoff valve 52 are opened, and the first shutoff valve 12 is closed to close the blast furnace 102. The exhaust gas in the c) is maintained by the gas amount regulating valve 46 to be discharged through the discharge means 70.

That is, since the exhaust gas generated during the air-vent operation contains a large amount of dust, it is burned by the combustion means 30 to remove dust, but nitrogen and steam, which do not contain dust, are discharged gas during the purging as described above. At this time, the main pressure is maintained through the bypass pipe 50 and there is no fear of air pollution even when discharged to the discharge means 50.

Subsequently, when the hot air flow opening 111 is started to start a blowing operation, the hot air supplied into the blast furnace 102 is then mixed with steam and nitrogen in the blast furnace 102 and the bypass pipe through the gas amount control valve 46. It is discharged to the discharge means 70 via the 50.

At this time, the oxygen concentration detector 44 installed in the gas recovery pipe 10 detects the oxygen concentration and when the oxygen concentration is within the reference value (1%) to drain the water of the water sealing valve 108a to a drain valve (not shown). By discharging through and closing the gas amount control valve 46 to allow the gas to flow into the gas reservoir 110 and performing a blow operation to charge the charge into the blast furnace 108 to produce a molten iron.

While the invention has been shown and described with respect to particular embodiments, it will be appreciated that the invention can be varied and modified without departing from the spirit or scope of the invention as set forth in the claims below. It will be appreciated that those skilled in the art can easily know.

As described above, according to the present invention, by removing the dust in the exhaust gas discharged into the atmosphere during the operation of the air by the combustion means 30 to prevent the emission of dust to the atmosphere to prevent air pollution and clean the working environment Can get the effect.

1 is a schematic diagram showing gas flow during operation in a blast furnace;

Figure 2 is a schematic view of the dust removal apparatus during the operation of the blast furnace, blowing operation according to the present invention;

Figure 3 is a detailed view of the dust removal device during the blast, blow operation of the blast furnace according to the present invention.

Explanation of symbols on the main parts of the drawings

10 ..... Gas recovery line 12 ..... 1st shutoff valve

30 ..... combustion means 31 ..... burners

32 ..... flue gas discharge pipe 33 ..... case

34 ..... 3rd shutoff valve 38 ..... pipe

50 ..... bypass 52 ..... 2nd shutoff valve

70 ..... Means of discharge 72 ..... Heat exchanger

102 ..... blast furnace 104 ..... dry damper

106 ..... wet damper 108 ..... gas piping

108a ..... Subongsa 110 ..... Gas reservoir

Claims (3)

A gas pipe 108 having a water seal side 108a is installed at the rear end of the gun and the wet dampers 104 and 106 connected to the blast furnace 102, and the gas reservoir 110 is connected to the gas pipe 108 to provide In the device for preventing the discharge of dust contained in the gas discharged during the holiday, blowing operation, A gas recovery pipe 10 connected to the front end of the water sealing side 108a and provided with a first shutoff valve 12; Combustion means (30) installed in the gas recovery pipe (10); And A bypass pipe (50) branched from the front end of the combustion means (30) and provided with a second shutoff valve (52) to communicate with the gas recovery pipe (10); Device for removing dust during the operation of the blast furnace, blowing, characterized in that the combustion of dust contained in the discharged gas, including. The method of claim 1, wherein the combustion means 30 is connected to the discharge means 70 for discharging gas, the heat exchanger 72 is disposed between the combustion means 30 and the discharge means 70 The bypass pipe 50 is connected to the heat exchanger 72 and the discharge means 70, characterized in that the dust removal device during the shelter, blow operation of the blast furnace, characterized in that connected. 3. The blast furnace according to claim 1 or 2, wherein the combustion means (30) comprises a case (33) and a burner (31) disposed in the case for fueling coke oven gas (COG). Dust removal device in case of work and ventilation.