Dust collecting device

Abstract

To provide a dust collector capable of preventing corrosion of an injector pipe by corrosive gas with a simple structure without causing complication of a structure or a cost increase.SOLUTION: In a dust collector 1, in which an inside of a body 2 is divided by a partition wall 3 into a dust chamber S1 and a purified gas chamber S2, a bag filter 6 is fitted to the partition wall 3, and an injector pipe 12 extending from a compressed air supply source installed outside the body 2 is introduced into the purified gas chamber S2, the injector pipe 12 is provided with corrosive gas retention preventing means (for example, an atmosphere open hole 12a) for preventing the retention of the corrosive gas in an exposed part exposed outside the body 2 of the injector pipe 12.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a dust collector for removing dust contained in corrosive gases.

Background Art

[0002] For example, corrosive gases such as sulfur oxides (SO X ), hydrogen sulfide (H2S), and hydrogen chloride (HCl) that corrode metals are discharged from blast furnaces, electric furnaces, waste treatment furnaces, etc. Since this corrosive gas contains dust, this dust is removed by a dust collector.

[0003] As the above dust collector, one using an outer surface filtration type bag filter is generally used (see, for example, Patent Document 1). In this type of dust collector, the corrosive gas flows from the outside to the inside of the bottomed cylindrical (bag-shaped) bag filter, and the dust contained in the corrosive gas is removed (collected). Therefore, as the dust collection progresses, dust adheres to the outer peripheral surface of the bag filter, and as a result, the ventilation resistance (pressure loss) of the corrosive gas passing through the bag filter increases, and the processing capacity of the dust collector decreases.

[0004] Therefore, high-pressure compressed air is instantaneously and sequentially injected into each bag filter from an air injection port opening to an injector pipe, and the dust adhering to the outer peripheral surface of the bag filter is periodically removed (backwashed).

[0005] However, in the dust collector equipped with the above backwashing function, during normal operation other than during backwashing of the bag filter, since the air injection port of the injector pipe is always open, the corrosive gas flows into the injector pipe from the air injection port and stays. When the staying corrosive gas is cooled to a temperature below the dew point, it liquefies and corrodes the inner peripheral surface of the injector pipe, so that the durability of the injector pipe decreases.

[0006] Therefore, Patent Document 2 proposes a dust collector (pulse bag filter device) that prevents the inflow of corrosive gas into the injector pipe and prevents corrosion of the injector pipe by bypassing the compressed air (for corrosive gas purge) from the compressor through the header and diaphragm valve and flowing it into the injector pipe (injection pipe) at all times (even outside the reverse washing time of the bag filter).

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0008] However, in the dust collector proposed in Patent Document 2, since it is necessary to drive the compressor constantly to flow the compressed air into the injector pipe even outside the reverse washing time, there is a problem that the power consumption increases and the running cost becomes high. In addition, since valves and bypass pipes are required to bypass the compressed air through the header and diaphragm valve and flow it into the injector pipe constantly, there is also a problem that the structure becomes complicated and the equipment cost increases.

[0009] The present invention has been made in view of the above problems, and an object thereof is to provide a dust collector that can prevent corrosion of an injector pipe due to a corrosive gas with a simple configuration without causing complication of the structure and cost increase.

Means for Solving the Problems

[0010] To achieve the above object, the present invention divides the inside of the main body into a dust collection chamber and a purified gas chamber by a partition wall, attaches a bag filter to the partition wall, A dust collecting device that introduces an injector pipe extending from a compressed air supply source installed outside the main body into the purified gas chamber, characterized in that corrosive gas retention prevention means for preventing the retention of corrosive gas in the exposed portion of the injector pipe that is exposed outside the main body is provided in the injector pipe.

[0011] Here, the Rotten corrosive gas retention prevention means includes an air release hole that opens in the exposed portion of the injector pipe, a box-shaped retreat portion formed in the exposed portion of the injector pipe, and an air release hole formed in the retreat portion, an on-off valve or a check valve provided at the air injection port of the injector pipe, an on-off valve or a check valve provided at a position upstream of the air injection port of the injector pipe, and the like.

Advantages of the Invention

[0012] According to the present invention, during normal operation (dust collection) other than the reverse cleaning of the dust collecting device, in the exposed portion of the injector pipe that is exposed outside the main body, the retention of corrosive gas inside the exposed portion is prevented by the corrosive gas retention prevention means.

[0013] For example, when the corrosive gas retention prevention means is constituted by an air release hole that opens in the exposed portion of the injector pipe, outside air is drawn into the injector pipe from the air release hole due to the negative pressure inside the injector pipe to prevent the retention of corrosive gas in the injector pipe. Therefore, the corrosive gas is not cooled and liquefied (does not become an acidic liquid) inside the exposed portion of the injector pipe, corrosion of the injector pipe is prevented, and the durability of the injector pipe is enhanced.

[0014] In addition, since the corrosive gas retention prevention means simply forms an air release hole in the exposed portion of the injector pipe, it can be provided compactly and simply on the injector pipe itself, without causing complication of the structure of the dust collecting device or cost increase, and the running cost can also be kept low.

Brief Description of the Drawings

[0015]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Embodiments for Carrying Out the Invention

[0016] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0017] <Embodiment 1> FIG. 1 is a longitudinal sectional view showing the state during normal operation (dust collection) of the dust collector according to Embodiment 1 of the present invention, FIG. 2 is an enlarged detailed view of part A in FIG. 1, and FIG. 3 is an enlarged detailed view of part B in FIG. 2. As shown in FIG. 1, the dust collector 1 according to this embodiment includes a main body (housing) 2 in the shape of a sealed container. The interior of the main body 2 is partitioned by a horizontal partition wall 3 into a lower dust collection chamber S1 and an upper purified gas chamber S2. Here, the volume of the dust collection chamber S1 is set to be larger than the volume of the purified gas chamber S2, and the lower part of the main body 2 is formed in a funnel shape that becomes narrower downward. A dust discharge port 2a is opened at the lower end of the main body 2, and a rotary valve 4 for opening and closing the dust discharge port 2a is provided at the dust discharge port 2a. Further, a gas inlet pipe 5 is connected to the lower part of the main body 2. One end of the gas inlet pipe 5 is connected to a blast furnace, an electric furnace, a waste treatment furnace, etc. (not shown) that discharge corrosive gas, and the other end is connected to the lower part of the main body 2 of the dust collector 1 as described above and opens into the dust collection chamber S1 in the main body 2.

[0018] By the way, in the dust collection chamber S1 in the main body 2, a plurality of bag filters 6 in the shape of a bottomed cylinder ( ( bag shape) with a closed lower end are accommodated. Here, each bag filter 6 is vertically suspended with its upper end supported by the partition wall 3, and its upper end is tapered upward, and the upper end opening 6a opens into the purified gas chamber S2.

[0019] On the other hand, a gas outlet pipe 7 is connected to the side of the purified gas chamber S2 formed in the upper part of the main body 2. One end of the gas outlet pipe 7 opens into the purified gas chamber S2, and the other end is connected to a suction fan 8.

[0020] Incidentally, the dust collector 1 according to the present embodiment is provided with a backwashing device 10 for periodically removing dust adhering to the outer peripheral surface of each bag filter 6 by using high-pressure compressed air. This backwashing device 10 includes a compressor (not shown) which is a compressed air supply source installed outside the main body 2, a header 11 for temporarily storing the high-pressure compressed air discharged from the compressor, an injector pipe 12 extending from the header 11, a diaphragm valve 13 provided near the header 11 of the injector pipe 12, a solenoid valve box 14 attached to the header 11, and the like. The solenoid valve box 14 houses a solenoid valve (not shown), and this solenoid valve is connected to the diaphragm valve 13 via an air bleed pipe 15. Further, in the present embodiment, an SGP pipe (carbon steel pipe for piping) is used for the injector pipe 12.

[0021] Here, the injector pipe 12 includes a vertical portion 12A extending vertically downward from the diaphragm valve 13, and a horizontal portion 12B bent at a right angle from the lower end of the vertical portion 12A toward the main body 2 and extending horizontally. A part of the vertical portion 12A and the horizontal portion 12B of this injector pipe 12 (a portion close to the vertical portion 12A) constitutes an exposed portion exposed outside the main body 2.

[0022] The horizontal portion 12B of the injector pipe 12 is introduced into a purification gas chamber S2 formed in the upper part of the main body 2 and extends horizontally in the purification gas chamber S2. And at a plurality of locations of this horizontal portion 12 of the injector pipe 12 (positions facing the upper end openings 6a of the respective bag filters 6), air injection ports (not shown) opening toward the upper end openings 6a of the respective bag filters 6 are respectively opened, and air injection nozzles 16 are respectively attached to the respective air injection ports. Therefore, the plurality of air injection nozzles 16 are respectively opened toward the upper end openings 6a of the plurality of bag filters 6. B of a plurality of locations (positions facing the upper end openings 6a of each bag filter 6), air injection ports (not shown) opening toward the upper end openings 6a of each bag filter 6 are respectively opened, and air injection nozzles 16 are respectively attached to the respective air injection ports. Therefore, the plurality of air injection nozzles 16 are respectively opened toward the upper end openings 6a of the plurality of bag filters 6.

[0023] Incidentally, in the dust collector 1 according to the present embodiment, corrosive gas retention prevention means is provided to prevent the retention of corrosive gas inside the exposed portion (mainly the vertical portion 12A) of the injector pipe 12 that is exposed outside the main body 2. This corrosive gas retention prevention means is for preventing the corrosive gas introduced into the dust collection chamber S1 inside the main body 2 during the normal operation (dust collection) of the dust collector 1 from flowing into the injector pipe 12 and staying inside the exposed portion (mainly the vertical portion 12A) that is exposed outside the main body 2 of the injector pipe 12. In the present embodiment, as shown in FIGS. 2 and 3, it is constituted by an air release hole 12a formed at the upper end portion of the injector pipe 12 near the diaphragm valve 13. Note that a heat insulating material for suppressing the cooling of the vertical portion 12A is wound around the outer periphery of the vertical portion 12A that is exposed outside the main body 2 of the injector pipe 12.

[0024] Next, the operations of the dust collector 1 configured as described above during normal operation (dust collection) and backwashing will be described below, respectively. 1) Operation during normal operation (dust collection): During the normal operation (dust collection) of the dust collector 1, the rotary valve 4 provided at the lower end portion of the main body 2 is closed, and the backwashing device 10 is in a stopped (non-operating) state. When the suction fan 8 is rotationally driven in this state, both the dust collection chamber S1 and the purified gas chamber S2 inside the main body 2 become negative pressure, and the corrosive gas discharged from a waste treatment furnace (not shown) and the like is drawn by this negative pressure and flows into the dust collection chamber S1 inside the main body 2 from the gas inflow pipe 5 as shown by the arrow in FIG. 1.

[0025] As described above, the dust collection chamber S 1 The corrosive gas that has flowed into it passes through each of the plurality of bag filters 6, and the dust contained therein is collected by each bag filter 6 and adheres to the outer peripheral surface of each bag filter 6. Then, the corrosive gas from which the dust has been removed and purified is discharged from the upper end opening 6a of each bag filter 6 into the purified gas chamber S2 as shown by the arrow in FIG. 1, flows out of the main body 2 from the gas outflow pipe 7, is sucked by the suction fan 8, and is sent to a treatment device (not shown).

[0026] Incidentally, during normal operation of the dust collector 1, since each air injection nozzle 16 installed in the horizontal portion 12B of the injector pipe 12 is always open to the purified gas chamber S2, there is a concern that corrosive gas in the purified gas chamber S2 may flow into the inside of the injector pipe 12 from each air injection nozzle 16 and cause the problems described above. However, in the present embodiment, as shown in FIGS. 2 and 3, as a means for preventing the retention of corrosive gas, an atmosphere release hole 12a is formed in the vertical portion 12A exposed to the outside of the main body 2 of the injector pipe 12. Therefore, the above-described problems do not occur for the following reasons.

[0027] That is, since the pressure in the purified gas chamber S2 in the main body 2 is maintained at a negative pressure as described above, the inside of the injector pipe 12 communicating with the purified gas chamber S2 via the air injection nozzle 16 is also maintained at a negative pressure. Therefore, the outside air is drawn into the injector pipe 12 from the atmosphere release hole 12a as shown by the arrow in FIG. 1 due to the negative pressure in the injector pipe 12. Then, the outside air that has flowed into the injector pipe 12 flows toward the horizontal portion 12B inside the injector pipe 12 and flows out from each air injection nozzle 16 installed in the horizontal portion 12B into the purified gas chamber S2. For this reason, the corrosive gas in the purified gas chamber S2 does not flow into the injector pipe 12 through each air injection nozzle 16, and as a result of the corrosive gas staying and being cooled in the exposed portion (mainly the vertical portion 12A) of the injector pipe 12 as in the prior art, the problem that this corrosive gas liquefies and corrodes the inner peripheral surface of the injector pipe 12 does not occur, and for this reason, the durability of the injector pipe 12 is enhanced.

[0028] When the above-described dust collection action is repeated, dust gradually adheres to and accumulates on the outer peripheral surface of each bag filter 6, the ventilation resistance of the corrosive gas passing through each bag filter 6 increases, and the dust collection function of each bag filter 6 deteriorates. For this reason, when it is detected by a pressure gauge (not shown) that the ventilation resistance of the corrosive gas passing through each bag filter 6 has reached a predetermined value, or after a predetermined time has elapsed, the backwashing device 10 is driven and each bag filter 6 is backwashed with compressed air.

[0029] Next, the operation of the dust collector 1 during backwashing will be described below with reference to FIG. 4. 2) Operation during backwashing: FIG. 4 is a longitudinal sectional view showing the state of the dust collector 1 according to the present embodiment during backwashing. The backwashing of each bag filter 6 is performed as follows by driving the backwashing device 10. That is, a compressor (not shown) is driven, and the high-pressure compressed air discharged from the compressor is temporarily stored in the header 11. For example, every time a predetermined time elapses, a solenoid valve (not shown) housed in the solenoid valve box 14 is opened, so that the diaphragm valve 13 is opened via the vent pipe 15, and the compressed air stored in the header 11 flows out to the injector pipe 12.

[0030] Then, as shown in FIG. 4, the high-pressure compressed air flows in the injector pipe 12 in the direction of the arrow shown in the figure, and the compressed air is instantaneously injected from each air injection nozzle 16 toward the upper end opening 6a of each bag filter 6, and the dust adhering to the outer peripheral surface of each bag filter 6 is blown off and removed. Then, the dust blown off from the outer peripheral surface of each bag filter 6 falls inside the dust collection chamber S as shown by the arrow in FIG. 4, is collected at the lower part of the main body 2, and is discharged and recovered from the main body 2 to the outside through the dust discharge port 2a when the rotary valve 4 is opened. Incidentally, when the compressed air flows through the injector pipe 12 at high speed during this backwashing, the static pressure decreases by the amount of the dynamic pressure of this compressed air, so that the inside of the injector pipe 12 becomes a negative pressure. For this reason, the outside air is sucked into the injector pipe 12 from the atmosphere opening hole 12a, and the sucked outside air flows through the injector pipe 12 together with the compressed air flowing there and is used for backwashing each bag filter 6. 1 As is clear from the above description, according to the dust collector 1 according to the present embodiment, during normal operation (dust collection) other than during backwashing, the exposed portion (mainly the vertical portion 12A) of the injector pipe 12 exposed to the outside of the main body 2

[0031] ) insideRetention of corrosive gas is prevented by outside air flowing into the injector pipe 12 from the air vent hole 12a formed in the injector pipe 12. For this reason, the corrosive gas is not cooled and liquefied (it does not become an acidic liquid) inside the exposed portion (mainly the vertical portion 12A) of the injector pipe 12, and corrosion of the injector pipe 12 made of an SGP pipe is prevented, resulting in an effect of enhancing the durability of the injector pipe 12.

[0032] Also, the means for preventing retention of corrosive gas is simply formed by the air vent hole 12a in the exposed portion (vertical portion 12A) of the injector pipe 12, and is provided in a compact and simple manner in the injector pipe 12 itself. Therefore, there is no complication of the structure of the dust collector 1 or increase in cost, and an effect of keeping the running cost low can also be obtained.

[0033] <Embodiment 2> Next, Embodiment 2 of the present invention will be described below with reference to FIGS. 5 and 6.

[0034] FIG. 5 is a longitudinal sectional view of a main part of the dust collector according to Embodiment 2 of the present invention (a view similar to FIG. 2), and FIG. 6 is an enlarged detailed view of part C in FIG. 5. In these figures, the same reference numerals are given to the same elements as those shown in FIGS. 2 and 3, and repeated description thereof will be omitted below.

[0035] In the dust collector 1A according to the present embodiment, the means for preventing retention of corrosive gas is constituted by a box-shaped retraction portion 17 formed at the upper part of the vertical portion 12A which is the exposed portion of the injector pipe 12, and an air vent hole 17a opening in the lower surface of the retraction portion 17. Other configurations are the same as those of the dust collector 1 (see FIG. 1) according to Embodiment 1. Here, the retraction portion 17 communicates with the inside of the vertical portion 12A of the injector pipe 12.

[0036] Also in the dust collector 1A according to the present embodiment, the dust collection by the bag filter 6 and the backwashing of the bag filter 6 are performed in the same manner as the dust collector 1 according to the first embodiment. However, the inflow of the corrosive gas into the injector pipe 12 during dust collection is performed as shown by the arrows in FIGS. 5 and 6, in which the outside air is drawn by the negative pressure in the injector pipe 12 and flows into the inside of the injector pipe 12 through the inside of the evacuation portion 17 from the atmosphere release hole 17a.

[0037] Therefore, also in the present embodiment, the corrosive gas is not cooled and liquefied (does not become an acidic liquid) in the exposed portion (mainly the vertical portion 12A) of the injector pipe 12, and the corrosion of the injector pipe 12 made of the SGP pipe is prevented, and the durability of the injector pipe 12 is improved.

[0038] In addition, the means for preventing the retention of the corrosive gas is simply formed by the evacuation portion 17 and the atmosphere release hole 17a in the exposed portion (vertical portion 12A) of the injector pipe 12, and is provided in a compact and simple manner on the injector pipe 12 itself. Therefore, the structure of the dust collector 1A is not complicated and the cost is not increased, and the effect that the running cost can be kept low is also obtained.

[0039] <Embodiment 3> Next, Embodiment 3 of the present invention will be described below with reference to FIG. 7.

[0040] FIG. 7 is a longitudinal sectional view of the dust collector according to Embodiment 3 of the present invention. In this figure, the same elements as those shown in FIGS. 1 to 6 are denoted by the same reference numerals, and the repeated description thereof will be omitted below.

[0041] In the present embodiment related toThe dust collector 1B is characterized in that the corrosive gas retention prevention means is constituted by an on-off valve 18A or a check valve 18B provided respectively at an air injection port (not shown) that opens to the horizontal portion 12B of the injector pipe 12, and other configurations are the same as those of the dust collector 1 (see FIG. 1) according to the first embodiment. Here, the on-off valve 18A is constituted by an electric valve, a solenoid valve, etc. that are controlled to open and close by a controller (not shown). Further, the check valve 18B functions to prevent the inflow of corrosive gas into the injector pipe 12 and allow the injection of compressed air for backwashing into the bag filter 6.

[0042] Also in the dust collector 1B according to the present embodiment, the dust collection by the bag filter 6 and the backwashing of the bag filter 6 are performed in the same manner as in the dust collector 1 (see FIG. 1) according to the first embodiment. However, the inflow of corrosive gas into the injector pipe 12 during dust collection is surely prevented by closing the on-off valve 18A or by the check valve 18B preventing the flow of corrosive gas. During the backwashing of the bag filter 6, since the on-off valve 18A is opened, compressed air passes through the on-off valve 18A or the check valve 18B and is respectively injected toward each bag filter 6 to be used for the backwashing of these bag filters 6.

[0043] Therefore, also in the present embodiment, corrosive gas does not stay in the exposed portion (mainly the vertical portion 12A) of the injector pipe 12, and the staying corrosive gas is not cooled and liquefied. For this reason, the corrosion of the injector pipe 12 constituted of SGP pipe is prevented, and the effect that the durability of the injector pipe 12 is enhanced can be obtained.

[0044] Further, since the corrosive gas retention prevention means is simply configured by only providing the on-off valve 18A or the check valve 18B on the injector pipe 12 itself, the structure of the dust collector 1B is not complicated and the cost is not increased, and the effect that the running cost can also be kept low can be obtained.

[0045] <Embodiment 4> Next, Embodiment 4 of the present invention will be described below with reference to FIG. 8.

[0046] FIG. 8 is a longitudinal sectional view of the dust collector according to Embodiment 4 of the present invention. In this figure, the same elements as those shown in FIGS. 1 to 4 are denoted by the same reference numerals, and the repeated description thereof will be omitted below.

[0047] In this embodiment related to The dust collector 1C is characterized in that the means for preventing the retention of corrosive gas is constituted by an on-off valve 19A or a check valve 19B provided at the base end portion (the right end portion in FIG. 8) of the horizontal portion 12B facing the purified gas chamber S2 of the injector pipe 12, that is, at a position upstream (upstream in the flow direction of compressed air) of an air injection port (not shown) of the injector pipe 12. Other configurations are the same as those of the dust collector 1 (see FIG. 1) according to Embodiment 1. Specifically, in Embodiment 3, on-off valves 18A or check valves 18B were respectively provided at the air injection ports of the respective bag filters 6 of the injector pipe 12, whereas in this embodiment, one on-off valve 19A or check valve 19B is provided at the base end portion (the portion upstream of the air injection port) of the portion introduced into the purified gas chamber S2 of the injector pipe 12. Here, the on-off valve 19A is constituted by an electric valve, an electromagnetic valve, etc. that are opened and closed under the control of a controller (not shown). Further, the check valve 19B functions to prevent the flow of the corrosive gas flowing into the injector pipe 12 from going toward the vertical portion 12A of the injector pipe 12 and to allow the passage of the compressed air for backwashing.

[0048] Also in the dust collector 1C according to the present embodiment, the dust collection by the bag filter 6 and the backwashing of the bag filter 6 are performed in the same manner as the dust collector 1 according to the first embodiment. However, during dust collection, the on-off valve 19A is closed, and the flow of the corrosive gas flowing into the horizontal portion 12B of the injector pipe 12 in the direction of the vertical portion 12A is blocked by the on-off valve 19A or the check valve 19B. During the backwashing of the bag filter 6, since the on-off valve 19A is opened, the compressed air passes through the on-off valve 19A or the check valve 19B and is jetted toward each bag filter 6 to be used for the backwashing of these bag filters 6.

[0049] Therefore, also in the present embodiment, corrosive gas does not stay in the exposed portion (mainly the vertical portion 12A) of the injector pipe 12, and the staying corrosive gas is not cooled and liquefied. For this reason, corrosion of the injector pipe 12 composed of the SGP pipe is prevented, and the effect that the durability of the injector pipe 12 is enhanced can be obtained.

[0050] In addition, since the corrosive gas retention prevention means is simply configured by providing only the on-off valve 19A or the check valve 19B on the injector pipe 12 itself, only one on-off valve 19A or check valve 19B is required. Compared with the third embodiment, the number of parts can be reduced and the structure can be simplified, and the structure of the dust collector 1C is not complicated and the cost is not increased, and the running cost can also be kept low.

[0051] Note that the present invention is not limited to the embodiments described above, and various modifications can be made within the scope of the technical idea described in the claims, the specification, and the drawings.

Explanation of reference numerals

[0052] 1, 1A to 1C Dust collector 2 Main body 3 Partition wall 4 Rotary valve 5 Gas inlet pipe 6 Bag filter Upper end opening of the 6a bug filter 7 Gas outflow pipe 8 Suction fan 10 Backwashing device 11 Header 12 Injector pipe 12A Vertical part of the injector pipe 12B Horizontal part of the injector pipe 12a Atmosphere release hole (means for preventing corrosive gas retention) 13 Diaphragm valve 16 Air injection nozzle 17 Retreating part (means for preventing corrosive gas retention) 17a Atmosphere release hole (means for preventing corrosive gas retention) 18A, 19A On-off valve (means for preventing corrosive gas retention) 18B, 19B Check valve (means for preventing corrosive gas retention) S1 Dust collection chamber S2 Purified gas chamber

Claims

1. The interior of the main body is partitioned by a partition wall into a dust collection chamber and a purified gas chamber, A bag filter opening into the purified gas chamber is attached to the partition wall, A dust collection device that introduces an injector pipe extending from a compressed air supply source installed outside the main body into the purified gas chamber, Corrosive gas retention prevention means for preventing the retention of corrosive gas in an exposed portion of the injector pipe that is exposed outside the main body is provided in the injector pipe, The corrosive gas retention prevention means is formed at a position where the inside of the injector pipe becomes negative pressure when compressed air from the compressed air supply source flows through the injector pipe, A dust collection device characterized by the above.

2. The interior of the main body is partitioned by a partition wall into a dust collection chamber and a purified gas chamber, A bag filter opening into the purified gas chamber is attached to the partition wall, A dust collection device that introduces an injector pipe extending from a compressed air supply source installed outside the main body into the purified gas chamber, Corrosive gas retention prevention means for preventing the retention of corrosive gas in an exposed portion of the injector pipe that is exposed outside the main body is provided in the injector pipe, The corrosive gas retention prevention means is formed at a position close to a valve that causes compressed air from the compressed air supply source to flow out into the injector pipe, A dust collection device characterized by the above.

3. The interior of the main body is partitioned by a partition wall into a dust collection chamber and a purified gas chamber, A bag filter opening into the purified gas chamber is attached to the partition wall, A dust collection device that introduces an injector pipe extending from a compressed air supply source installed outside the main body into the purified gas chamber, Corrosive gas retention prevention means for preventing the retention of corrosive gas in an exposed portion of the injector pipe that is exposed outside the main body is provided in the injector pipe, The injector pipe includes a vertical portion that extends vertically downward from a valve that allows compressed air from the compressed air supply source to flow out into the injector pipe. The corrosive gas retention prevention means is formed at the upper end of the vertical portion. A dust collector characterized by the above.

4. The dust collector according to any one of claims 1 to 3, wherein the corrosive gas retention prevention means is constituted by an air release hole that opens to the exposed portion of the injector pipe.

Images