WO2013179371A1

WO2013179371A1 - Soot removal device within flow path and dust collection device

Info

Publication number: WO2013179371A1
Application number: PCT/JP2012/063626
Authority: WO
Inventors: 暁村井; 康史奥田; 田中　敏彦
Original assignee: 三菱重工プラント建設株式会社
Priority date: 2012-05-28
Filing date: 2012-05-28
Publication date: 2013-12-05
Also published as: JPWO2013179371A1; JP5272111B1; IN2014MN02148A

Abstract

Provided is a soot removal device, disposed in a flow path through which a fluid flows, for the purpose of removing dust contained in the fluid and deposited in the flow path, while circulating the fluid through the flow path, said soot removal device being provided with: a suction pipe (20) that extends outward from a flow path casing (4) and has an open leading end (21) facing a removal part (3) from which dust is to be removed, said suction pipe (20) being connected to a suction means (9) at the base end side; and a drive means (23) for causing forward and backward movement of the opening of the suction pipe (20) in the flow path.

Description

Passage removal device and dust collection device

The present invention relates to an in-flow passage dedusting device and a dust collecting device.

For example, in order to remove nitrogen oxides (NOx) in exhaust gas containing dust discharged from a thermal power plant, a flue gas denitration method using a selective catalytic reduction reaction using ammonia (NH ₃ ) as a reducing agent is used. Yes. In this selective catalytic reduction reaction, NH ₃ is injected into NOx contained in the exhaust gas and reduced by a denitration catalyst. Specifically, denitration is performed by arranging a lattice-shaped denitration catalyst in a flow path through which exhaust gas flows such as an exhaust duct or a flow path casing connected to the exhaust duct.

The exhaust gas from a thermal power plant that uses coal as fuel contains a large amount of dust and other dust as unburned components, which causes clogging of the denitration catalyst. In order to solve this problem, for example, a technique is known in which soot is blown off along the flow direction of exhaust gas by using a removal apparatus (suit blower) as described in Patent Document 1, for example.

JP-A-62-69015

By the way, depending on the nature of the coal, the operating conditions of the boiler, etc., a lump of soot is formed in the exhaust gas (particle diameter is several mm to several tens of mm) larger than the gas narrow flow path of the denitration catalyst (hereinafter referred to as popcorn ash) The problem is that popcorn ash is clogged with the denitration catalyst and clogs the fine channels formed in a lattice shape in the denitration catalyst. Unlike particulate soot, popcorn ash is larger than the gas flow path of the denitration catalyst, so it cannot be blown off along the flow direction of exhaust gas with a conventional denitrification device. It was necessary to clean it manually.

The present invention has been made in consideration of such circumstances, and its object is to provide a flow path capable of removing dust that is difficult to remove by spraying, such as popcorn ash, while the fluid is circulated in the flow path. An object of the present invention is to provide an internal dust removal device and a dust collection device.

In order to solve the above problems, the present invention provides the following means.
An in-flow channel decontamination device of the present invention is provided in a flow path casing through which a fluid flows, and dust that is contained in the fluid and accumulates in the flow path casing is allowed to flow through the flow path casing. An in-flow channel degreasing device for removing, in order to suck the dust on the base end side while opening the front end facing the removal portion from which dust is removed, extending outward from the flow channel casing A suction pipe connected to the suction means, and a drive means for advancing and retracting the opening of the suction pipe in the flow path.

According to the above configuration, since dust is sucked and removed through the suction pipe, it is possible to prevent dust from accumulating on the removal portion.

In the above-described flow passage removing apparatus, the suction pipe includes a distal end pipe having the opening facing the removal portion, a proximal end connected to the suction unit, and a distal end inserted into the distal end pipe. It is preferable that the driving means advance and retract the tip tube.

According to the above configuration, the suction pipe is divided into a distal end tube that advances and retracts and a fixed proximal end tube, and the proximal end tube is inserted into the distal end tube to reduce the occupied area of the suction tube. In addition, it is possible to reduce the size of the in-channel removal apparatus.

In the in-channel removal apparatus, the driving means may be configured to advance and retract the distal end tube through a moving interlocking shaft provided along the distal end tube and the proximal end tube.

According to the above configuration, the system in which the gas containing the dust sucked by the tip tube flows is arranged away from the system including the driving means, and therefore it is possible to prevent the driving means from being damaged by the heat of the gas. .

In the above-described in-channel removal apparatus, it is preferable that the removal portion in the flow-path casing is provided with a net for capturing dust, and the opening of the suction pipe is provided to face the net.
According to the above configuration, it is possible to prevent dust larger than the mesh of the mesh from reaching the downstream side of the mesh.

In the above-mentioned flow path removal apparatus, it is preferable to include crushing means for crushing dust captured by the net.
According to the above configuration, the dust is more easily sucked by crushing the dust, and larger dust can be sucked by crushing the dust larger than the opening of the suction pipe.

In the in-flow path defoaming device, it is preferable to include a blowing means for blowing a dust removing gas to the removal portion.
According to the above configuration, the dust suction efficiency can be improved by blowing the dust removing gas to the dust to float the dust.

In the in-flow channel removing apparatus, the removing unit is a lattice-shaped denitration catalyst in which a plurality of narrow channels extend along the flow channel casing, and the suction pipe is provided on the upstream side of the denitration catalyst. Preferably it is.

In the above-described in-channel removal apparatus, it is preferable that a motor constituting the driving unit is provided apart from the suction pipe.
According to the said structure, damage to the motor by the heat | fever of the gas containing dust can be prevented.

In addition, the present invention provides any one of the above-described in-flow passage removal devices, a dust delivery pipe connected to the proximal end side of the suction pipe, a filter for capturing dust in the dust delivery pipe, and the suction means. A dust collecting device is provided.

According to the above configuration, by providing the filter in the dust delivery tube for discharging the dust, it is possible to supplement the dust sucked by the in-flow passage removing device.

The dust collection device preferably includes means for introducing a cooling gas on the dust delivery pipe and upstream of the filter.
According to the above configuration, it is possible to prevent high temperature fluid from reaching the filter by introducing cooling air to lower the temperature of the fluid.

According to the present invention, since dust is sucked and removed through the suction pipe, dust can be prevented from accumulating on the removal portion.

It is a systematic diagram of the dust collection | recovery apparatus which concerns on embodiment of this invention. It is a perspective view which shows the denitration catalyst of a dust collection | recovery apparatus. It is a side view of the in-channel removal apparatus according to the first embodiment of the present invention. It is A arrow line view of FIG. 3, and is a top view of the in-flow path dehulling device which concerns on 1st embodiment of this invention. It is the B section enlarged view of FIG. It is a side view of the in-channel removal device concerning a second embodiment of the present invention. It is the elements on larger scale explaining another form of the removal apparatus in a flow path. It is the elements on larger scale explaining further another form of the in-channel removal apparatus. It is the elements on larger scale explaining further another form of the in-channel removal apparatus.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
As shown in FIG. 1, the dust collection apparatus 1 of this embodiment is provided in the flow-path casing 4 connected with the exhaust duct 2a of the coal-fired boiler 2 of a thermal power plant, for example. The dust collecting apparatus 1 removes dust such as soot adhering to the denitration catalyst 3 (removal part) mounted inside the flow path casing 4, in particular, a lump of soot having a large particle diameter called popcorn ash. It is for removing while circulating the fluid.

At least one denitration catalyst 3 is mounted inside the flow passage casing 4 through which the exhaust gas as a fluid flows, and nitrogen oxide (NOx) contained in the exhaust gas comes into contact with the exhaust gas flowing through the flow passage casing 4. It is to reduce. For example, the denitration catalyst 3 is arranged at a predetermined interval so that the exhaust gas sequentially passes.

As shown in FIG. 2, the cross-sectional shape orthogonal to the exhaust gas flow direction F of the denitration catalyst 3 is a rectangular shape, and the flow path casing 4 has a shape in accordance with the shape of the denitration catalyst 3. The denitration catalyst 3 has a predetermined thickness in the flow direction. In the denitration catalyst 3, a plurality of narrow channels 3a along the flow direction F are formed in a grid pattern. The denitration catalyst 3 has a lattice shape as viewed from the flow direction F.

One end side and the other end side in the flow direction of the denitration catalyst 3 form a flat surface (hereinafter referred to as an end face 3b), and the plurality of narrow channels 3a extend so as to connect the end faces. The denitration catalyst 3 is mounted such that the end surface 3 b of the denitration catalyst 3 is orthogonal to the outer wall 4 a of the flow path casing 4.

As shown in FIG. 1, the dust collecting device 1 is fixed to the outer wall 4 a of the flow channel casing 4, and has at least one in-channel removal device 6 provided for one denitration catalyst 3. And a dust processing unit 5 for discharging the dust removed by the removal device 6.

The dust processing unit 5 includes a dust delivery pipe 7 for delivering a gas containing dust removed by the in-flow passage removing device 6 (hereinafter referred to as a gas), a bug filter 8 for supplementing the dust contained in the gas, It has a fan 9 as a suction means for generating a suction force in the in-flow path removal device 6 through the dust delivery pipe 7.
At least one dust processing unit 5 is provided in the dust collecting device 1 and configured to be able to process the dust sucked by the plurality of in-flow path removing devices 6.

The in-flow passage removing device 6 is a device that uses the negative pressure generated by the fan 9 to suck dust on the end surface 3 b of the denitration catalyst 3 mounted inside the flow passage casing 4. Details of the structure of the in-channel removal apparatus 6 will be described later.

Next, the dust processing unit 5 will be described. One dust processing unit 5 is provided for the plurality of in-flow path de-greasing devices 6, and it is possible to select which in-flow path de-dusting device 6 the suction force of the fan 9 is applied to.

The dust delivery pipe 7 is a pipe that connects the in-flow path deguiding device 6 and the fan 9. In the following description, the dust distribution pipe 7 will be described with the in-flow passage removal device 6 side as the upstream side and the fan 9 side as the downstream side. The gas flowing into the fan 9 from the upstream side is sent to the flue via the fan 9.

On the dust delivery tube 7, a bug filter 8 for supplementing the dust flowing through the dust delivery tube 7 is provided. As the bag filter 8, for example, a non-woven fabric can be used as a filter medium, and dust contained in the gas flowing through the dust delivery pipe 7 can be deposited on the non-woven fabric surface. The dust captured by the bag filter 8 is sent to the ash treatment facility.

A temperature transmitter 11 is provided on the upstream side of the bag filter 8, and the temperature of the gas introduced into the bag filter 8 is measured. The temperature transmitter 11 is connected to the temperature control device 12. An air introduction valve 13 capable of introducing air as a cooling gas is provided on the upstream side of the temperature transmitter 11. The air introduction valve 13 is connected to the temperature control device 12.
When the temperature of the gas measured by the temperature transmitter 11 exceeds a predetermined temperature (for example, 200 ° C.), the temperature control device 12 cools the dust delivery pipe 7 by opening the atmosphere introduction valve 13. The temperature of the gas can be lowered by introducing air as a gas.

A pressure transmitter 14 for measuring the pressure in the dust delivery pipe 7 is provided on the upstream side of the air introduction valve 13. The pressure transmitter 14 is connected to the pressure control device 15. A suction force control valve 16 is provided downstream of the bag filter 8 and upstream of the fan 9. The suction force control valve 16 is connected to the pressure control device 15.
The pressure control device 15 is set to adjust the suction force control valve 16 so that the gas pressure measured by the pressure transmitter 14 becomes a predetermined pressure.

The dust delivery pipe 7 on the upstream side of the pressure transmitter 14 is branched into a plurality of branch passages 7a, and each is connected to the in-flow passage removing device 6. A switching valve 17 is provided in each branch path 7a. The switching valve 17 is a valve that is opened and closed by a control device (not shown). The switching valve 17 generates a suction force of the fan 9 in the in-flow passage removing device 6 in the open state, and blocks the suction force of the fan 9 in the closed state.

Next, the detailed structure of the in-channel removal apparatus 6 will be described.
As shown in FIGS. 3 and 4, the in-flow channel removing device 6 has a lance tube 21 that is a tip tube inserted into the flow channel casing 4, and the tip is opened facing the denitration catalyst 3. A suction pipe 20 extending outward from the flow path casing 4, a housing 22 disposed outside the flow path casing 4 and accommodating a part of the suction pipe 20, and a drive mechanism 23 (drive means) for moving the lance tube 21 forward and backward ) As main components. The housing 22 has a rectangular tube shape. A terminal box 29 that accommodates a control board and the like is provided on the side surface of the housing 22.

The in-flow channel removing device 6 is attached to the outer wall 4 a of the flow channel casing 4 through a wall box 24. Further, the in-flow channel removing device 6 is attached so that the longitudinal direction of the lance tube 21 (hereinafter simply referred to as the longitudinal direction) is along the end surface 3 b of the denitration catalyst 3.

The suction pipe 20 has a lance tube 21 and a feed pipe 25 (base pipe) fitted into the lance tube 21. The feed pipe 25 is connected to the fan 9 (see FIG. 1) via the dust delivery pipe 7 on the base end side, that is, the side opposite to the lance tube 21 in the longitudinal direction. The feed pipe 25 is a circular tube-shaped member whose base end side is supported in a cantilever manner on the housing 22, and a distal end side is inserted into the circular tube-shaped lance tube 21.

The lance tube 21 is a circular tube-shaped member that is fitted to the distal end side of the feed pipe 25 and that can be moved forward and backward in the longitudinal direction by the drive mechanism 23. The lance tube 21 is composed of a lance tube main body 26 combined with the feed pipe 25 along the longitudinal direction, and a suction pipe portion 27 provided on the distal end side of the lance tube main body 26. Further, the lance tube 21 is inserted into the flow passage casing 4 through the wall box 24 while the distal end side including the suction pipe portion 27 protrudes to the outside of the housing 22.
The lance tube main body 26 is bent in the direction along the flow direction F of the flow path casing 4 and toward the denitration catalyst 3, and the suction pipe portion 27 is connected to the bent end portion. ing.

The suction pipe portion 27 has a circular tube shape like the lance tube main body 26, and its longitudinal direction is orthogonal to the longitudinal direction of the lance tube main body 26 and orthogonal to the flow direction F of the flow path casing 4. Is formed. That is, the suction pipe portion 27 is formed along the end surface 3 b of the denitration catalyst 3.

The both ends of the suction pipe part 27 are closed. A plurality of suction ports 28 are formed along the longitudinal direction of the suction pipe portion 27 on the side of the suction pipe portion 27 facing the denitration catalyst 3. The shape of the suction port 28 is an oval shape along the longitudinal direction of the suction pipe portion 27.

The drive mechanism 23 includes a traveling carriage 30 attached to the proximal end of the lance tube 21, a motor 33 provided outside the housing 22, and a sprocket and chain that transmits the power of the motor 33 to the traveling carriage 30. Have.

As shown in FIG. 5, a traveling carriage 30 that holds the lance tube 21 in a reciprocating manner along the longitudinal direction of the housing 22 is provided at the base end of the lance tube 21. The traveling carriage 30 holds the proximal end of the lance tube 21 and has a shape covering the outer periphery of the feed pipe 25, and has a function of keeping the airtightness between the lance tube 21 and the feed pipe 25. .

A sealing member 31 that seals between the inner peripheral surface of the traveling carriage 30 and the outer peripheral surface of the feed pipe 25 is provided on the contact surface of the traveling carriage 30 with the feed pipe 25. As the sealing member 31, for example, a gland packing can be employed.

Further, a guide roller 40 that travels on a guide rail 32 provided along the longitudinal direction of the housing 22 is attached to the traveling carriage 30, whereby a lance tube held by the traveling carriage 30 is installed. The movement along the longitudinal direction of 21 is enabled. Further, the guide roller 40 is provided at a position where it can abut on

limit switches

45 and 46, which will be described later, and turn the limit switch ON / OFF.

A motor 33 is disposed outside the housing 22 on the base end side of the housing 22. A first sprocket 34 is attached to the output shaft of the motor 33, and a second sprocket 35 is attached to the proximal end side inside the housing 22. A first chain 36 is hung on the first sprocket 34 and the second sprocket 35 so as to form an elliptical track. That is, the power of the motor 33 is transmitted via the first sprocket 34, the first chain 36, and the second sprocket 35 to the first rotating shaft 37 that rotatably supports the second sprocket 35.

A third sprocket 38 that rotates together with the second sprocket 35 is attached to a first rotating shaft 37 that is rotatably attached to the proximal end side of the housing 22. A second rotary shaft 39 is attached to the front end side of the housing 22 so as to avoid interference with the suction pipe 20, and a fourth sprocket 41 is rotatably attached to the second rotary shaft 39. Yes. A second chain 42 is hung on the third sprocket 38 and the fourth sprocket 41, whereby the second chain 42 forms an elliptical track along the longitudinal direction of the housing 22.
Further, the second chain 42 is coupled to the traveling carriage 30 via the connection member 43.

With the configuration as described above, when the power of the motor 33 is transmitted to the first rotating shaft 37, the third sprocket 38 rotates and the second chain 42 rotates on its track. Since the second chain 42 is connected to the traveling carriage 30, the traveling carriage 30 moves along the longitudinal direction when the second chain 42 travels on the track. That is, the lance tube 21 integrated with the traveling carriage 30 is moved along the longitudinal direction by the power of the motor 33.

A reverse limit switch 45 is provided on the distal end side of the housing 22, and a stop limit switch 46 is provided on the proximal end side of the housing 22. The limit switches 45 and 46 are arranged so that the switch is turned on when the guide roller 40 of the traveling carriage 30 comes into contact.
The limit switches 45 and 46 control the movement range of the lance tube 21 and the traveling carriage 30 and control the forward and reverse movements.

The wall box 24 includes a rectangular parallelepiped box body 47 and a seal box 48 attached to the base end side of the box body 47. The box body 47 is formed with a through hole 49 through which the lance tube 21 passes through a surface facing the distal end side and a surface facing the base end side opposite thereto. A predetermined gap is provided between the through hole 49 and the lance tube 21.

The seal box 48 is a rectangular parallelepiped box-like member, and is provided on the base end side of the box body 47. The seal box 48 is connected to a high pressure seal air supply pipe 50 for maintaining the inside of the seal box 48 at a high pressure. The air supplied from the high-pressure seal air supply pipe 50 flows into the box body 47 through a gap between the through hole 49 on the base end side of the box body 47 and the outer peripheral surface of the lance tube 21.
An attachment stay 51 extends on the proximal end side of the box body 47 and is connected to an attachment stay 52 provided on the distal end side of the housing 22. Further, a support roller 53 that supports the lance tube 21 from below is provided on the front end side of the housing 22.

Next, the operation of the dust collection device 1 according to this embodiment will be described.
First, when the motor 33 is activated, the second chain 42 travels by the rotational force of the motor 33, and the lance tube 21 extends along the longitudinal direction via the connecting member 43 and the traveling carriage 30 connected to the second chain 42. Moving. The lance tube 21 is controlled by a control device (not shown) so as to move forward in the direction of the distal end until the reverse limit switch 45 is turned on and to move backward until the stop limit switch 46 is turned on.

While the lance tube 21 moves, the dust on the denitration catalyst 3 is sucked and the gas containing the dust flows into the dust delivery pipe 7 through the feed pipe 25. The pressure of the gas is measured by the pressure transmitter 14, and the suction force control valve 16 is controlled according to this pressure, and the suction force is controlled.
Further, the temperature of the gas is measured by the temperature transmitter 11, and the air introduction valve 13 is controlled according to this temperature, and the temperature of the gas is controlled.
Next, dust contained in the gas is captured by the bag filter 8 and sent to the ash treatment facility. The gas from which the dust has been removed is sent to the flue via the fan 9.

According to the above-described embodiment, the dust adhering to the denitration catalyst 3, in particular, the lump of the soot having a large particle diameter such as popcorn ash is sucked and removed through the suction pipe 20 of the in-channel degutting device 6. Therefore, dust can be prevented from accumulating on the denitration catalyst 3. Thereby, the continuous operation time of a plant can be made longer.
Moreover, since the dust in the flow path casing 4 is discharged | emitted outside the flow path casing 4, cleaning of the flow path casing 4 at the time of a plant stop becomes easy.

In addition, since the gas containing dust sucked by the in-flow passage removing device 6 is introduced into the bag filter 8 through the dust delivery pipe 7, and the dust is removed by the bag filter 8, the dust reaches the atmosphere. Can be prevented.

Further, since the inside of the seal box 48 is maintained at a higher pressure than the inside of the flow path casing 4, it is possible to prevent the exhaust gas from leaking out from the insertion portion of the suction pipe 20.

Further, by providing a predetermined gap between the through hole 49 of the box body 47 of the wall box 24 and the lance tube 21, interference due to the difference in thermal expansion between the outer wall 4a and the lance tube 21 due to the heat of the exhaust gas is prevented. be able to.
In addition, since the motor 33 is disposed outside the housing 22 with respect to the suction pipe 20, damage to the motor 33 due to the heat of gas containing dust can be prevented.

In the above embodiment, the box body 47 is provided between the seal box 48 and the flow path casing 4, but the box body 47 of the wall box 24 may be omitted.

(Second embodiment)
Hereinafter, an in-flow channel removal apparatus according to a second embodiment of the present invention will be described with reference to the drawings.
As shown in FIG. 6, the in-flow channel removal apparatus 6 </ b> B according to the second embodiment has a suction pipe 20 and a wall box compared to the in-flow path removal apparatus 6 (see FIG. 3) of the first embodiment. The structure of 24B is different.

The suction pipe 20B of the present embodiment is provided in parallel with the moving interlocking shaft 55 that can be moved back and forth in the longitudinal direction by the drive mechanism 23, and the moving interlocking shaft 55, and the base end side is cantilevered to the wall box 24B. And a lance tube 21 </ b> B that is provided in parallel to the moving interlocking shaft 55 and connected to the moving interlocking shaft 55.

The front end side of the feed pipe 25B is inserted into the lance tube 21B. The moving interlocking shaft 55 passes through the wall box 24B and extends to the inside of the flow path casing 4, and the tip thereof is connected to the lance tube 21B. That is, the lance tube 21B is configured to advance and retract in the longitudinal direction when the moving interlocking shaft 55 advances and retracts.

At the base end of the lance tube 21B, the lance tube 21B can advance and retreat in a telescopic manner on the feed pipe 25B while sealing between the inner peripheral surface of the lance tube 21B and the outer peripheral surface of the feed pipe 25B. A sealing mechanism 56 is provided. A labyrinth seal 57 is provided on the contact surface of the seal mechanism 56 with the feed pipe 25B.

The lance tube 21B includes a lance tube main body 26B, a first suction pipe portion 58 provided at the tip of the lance tube main body 26B, and a second suction pipe portion 59 provided at the base end of the lance tube main body. Yes. That is, the lance tube 21B of the present embodiment has two

suction pipe portions

58, 59. The first suction pipe portion 58 is on one side in the longitudinal direction of the denitration catalyst 3, and the second suction pipe portion 59 is denitration. The other side in the longitudinal direction of the catalyst 3 is sucked.

Describing the operation of the in-channel removal apparatus 6B of the present embodiment, the movement interlocking shaft 55 advances and retreats in the longitudinal direction by driving the motor 33. As a result, the lance tube 21B connected to the moving interlocking shaft 55 advances and retreats in the longitudinal direction.

According to the above embodiment, the gas containing the dust sucked by the lance tube 21B is sent to the dust delivery pipe 7 without passing through the inside of the housing 22, so that the inside of the housing 22 is prevented from being damaged by the heat of the gas. can do.
Further, since the

suction pipe portions

58 and 59 are attached to the distal end and the proximal end of the lance tube 21B, the stroke of the lance tube 21B is substantially halved as compared with the in-flow passage deguiding device 6 of the first embodiment. can do.

FIG. 7 is a partially enlarged view for explaining another form of the in-flow channel degreasing device.
As shown in FIG. 7, another embodiment of the in-flow passage removing apparatus 6 </ b> C is provided with a wire net 61 that is a net for capturing dust on the upstream side of the denitration catalyst 3. The mesh of the wire mesh 61 is set to a size that can complement the large lump of candy such as popcorn ash and prevent passage of the cocoon lump. Further, the wire net 61 is disposed immediately before the denitration catalyst 3. The suction port 28 of the lance tube 21 is provided to face the wire mesh 61.

In addition, the lance tube 21 of the in-flow passage removing apparatus 6C of the present embodiment is provided with a brush 62 as a crushing means for crushing dust. Specifically, the brush 62 includes a support portion 63 that protrudes from the lance tube main body 26 toward the distal end side, and a number of metal wires 64 welded to the support portion 63, and the distal end of the wire 64 is the wire mesh 61. Projecting toward the metal mesh 61 and the denitration catalyst 3 side.

According to the above embodiment, it is possible to prevent a large lump of rice cake such as popcorn ash from reaching the denitration catalyst 3 disposed on the downstream side of the wire net 61, and the denitration catalyst 3 when the plant is stopped. Cleaning can be facilitated.
Further, by crushing dust having a large particle diameter with the brush 62, the dust is more easily sucked. Further, by crushing dust larger than the suction port 28, larger dust can be sucked.

FIG. 8 is a partially enlarged view for explaining still another embodiment of the in-flow passage removing apparatus, and is a plan view of the lance tube 21D and the suction pipe portion 27D as viewed from the direction along the flow direction F.
As shown in FIG. 8, the lance tube main body 26 of each of the above embodiments is connected to the suction pipe portion 27D of the in-flow passage removing apparatus 6D of the present embodiment, and high-pressure air that is a dust removing gas is used. Is connected to a second lance tube 66 that constitutes an injection pipe 65 that can be supplied so as to be sprayed onto the denitration catalyst 3.
The injection pipe 65 has substantially the same configuration as the suction pipe 20, but the suction pipe 20 sucks dust from the suction pipe portion 27D by the suction force of the fan 9, whereas the injection pipe 65 has a high-pressure air. Is different in that air is ejected from the suction port 28 of the suction pipe portion 27D.

According to the above aspect, in a stage before sucking dust, high-pressure air is ejected from the suction port 28 of the suction pipe portion 27D to make the dust floating, and it is easier to suck dust in the subsequent suction process. can do.

The form for supplying high-pressure air is not limited to this, and as shown in FIG. 9, a separate injection pipe portion 67 is provided, and an injection pipe 65 for supplying high-pressure air is connected to this injection pipe portion 67. It is good also as a structure. Moreover, as shown in FIG. 9, the injection pipe part 67 is good also as a structure which provides two so that the suction pipe part 27D may be pinched | interposed.
Further, the medium to be ejected is not limited to high-pressure air, and for example, high-pressure steam may be ejected to make the dust floating.

The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, the method for removing the dust contained in the gas is not limited to the bag filter, and the dust in the gas may be separated using a powder separator (cyclone). Or it is good also as a structure which throws in gas again in the location which does not have trouble in the process in a plant, without removing the dust in gas on the dust delivery pipe | tube 7. FIG.
Moreover, the dust collection device according to each of the above embodiments can collect not only popcorn ash but also various sizes of dust as long as it can be sucked by the suction pipe.

DESCRIPTION OF SYMBOLS 1 Dust collection apparatus 2 Boiler 2a Exhaust duct 3 Denitration catalyst 4 Flow path casing 5 Dust processing part 6 Passage removal device 7 Dust delivery pipe 8 Bag filter (filter)
9 Fan (suction means)
DESCRIPTION OF SYMBOLS 11 Temperature transmitter 12 Temperature control device 13 Atmospheric introduction valve 14 Pressure transmitter 15 Pressure control device 16 Suction force control valve 17 Switching valve 20 Suction tube 21 Lance tube (tip tube)
22 Housing 23 Drive mechanism (drive means)
24 Wall box 25 Feed pipe (base pipe)
33 Motor 61 Wire mesh

Claims

An in-channel dedusting device for removing dust contained in the fluid and deposited in the flow channel casing while circulating the fluid in the flow channel casing. There,
A suction pipe connected to a suction means for sucking dust on the base end side, with a distal end opening facing the removal portion from which dust is removed, extending outward from the flow path casing,
An in-channel removal apparatus comprising driving means for advancing and retracting the opening of the suction pipe in the channel.
The suction pipe is
A tip tube having the opening facing the removal portion;
A proximal end connected to the suction means, and a distal end inserted into the distal end tube;
2. The in-flow passage removing apparatus according to claim 1, wherein the driving means advances and retracts the tip tube.
3. The in-flow passage removing apparatus according to claim 2, wherein the driving means advances and retracts the distal end tube via a moving interlocking shaft provided along the distal end tube and the proximal end tube.
The removal portion in the flow path casing is provided with a net for capturing dust,
The in-flow passage deering apparatus according to any one of claims 1 to 3, wherein the opening of the suction pipe is provided to face the net.
5. The in-flow passage removing apparatus according to claim 4, further comprising a crushing means for crushing dust captured by the net.
6. The in-flow passage removing apparatus according to claim 1, further comprising a blowing unit that blows a dust removing gas to the removing unit.
2. The removal portion is a lattice-shaped denitration catalyst in which a plurality of narrow channels extend along the flow channel casing, and the suction pipe is provided on the upstream side of the denitration catalyst. The in-channel removal apparatus according to claim 6.
8. The in-flow passage removing apparatus according to any one of claims 1 to 7, wherein a motor constituting the driving means is provided apart from the suction pipe.
An in-flow passage removal apparatus according to any one of claims 1 to 8,
A dust delivery pipe connected to the proximal end side of the suction pipe;
A filter for capturing dust in the dust delivery pipe;
A dust collection device comprising the suction means.
The dust collection device according to claim 9, further comprising means for introducing a cooling gas on the dust delivery pipe and upstream of the filter.