JP2000015045A - Activated carbon packed tower - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the generation of dust from an activated carbon packed tower to replace the activated carbon packed tower properly and easily. SOLUTION: In an activated carbon packed tower 8 in stalled in an exhaust gas route 1 of waste treatment equipment, an activated carbon support floor 14 and a pressure sensor 30 to detect deterioration in an activated carbon C of a fixed bed 25 formed on the activated carbon support floor 14 are installed in a casing 11 provided with an activated carbon charging port 12 in the upper part and with an activated carbon discharging port 13 in the lower part. The activated carbon support floor 14 is composed of a plurality of rotatable mesh floors 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to activated carbon for removing harmful substances such as dioxins, heavy metals including mercury, nitrogen oxides, sulfur oxides, and hydrogen chloride contained in exhaust gas from waste treatment facilities. It relates to a packed tower.

[0002]

2. Description of the Related Art In a waste treatment facility for incinerating or melting waste, a dust collecting device for collecting exhaust gas dust in an exhaust gas path of a waste incinerator or a waste melting furnace;
An activated carbon packed tower for removing harmful substances such as dioxins and heavy metals including mercury, nitrogen oxides, sulfur oxides, and hydrogen chloride contained in exhaust gas is provided.

As shown in FIG. 3, a moving bed 42 of activated carbon C is formed in a casing 41 as a activated carbon packed tower which is disposed downstream of the dust collecting apparatus and used for removing the harmful substances. Activated carbon C is supplied from a hopper 43 provided on 41 to a moving bed 42 via a chute 44, and a discharge conveyor 47 is fed from the moving bed 42 via a roll feeder 45 below the casing 41 and a rotary valve 46.
4, a moving bed type activated carbon packed tower 40 for extracting activated carbon C, and a fixed layer 52 of activated carbon C is formed in a casing 51 as shown in FIG. Outlet 54
When the activated carbon C is deteriorated by the exhaust gas passing through the fixed layer 52, the used activated carbon C is discharged from the activated carbon outlet 54, and then the new activated carbon C is supplied from the activated carbon input hatch 53 to the fixed layer 52. An activated carbon packed tower 50 has been proposed.

However, in the moving bed type activated carbon packed tower 40,
Since the granular activated carbon C is moved in the moving layer 42 in the gas passing state, the activated carbon C is worn and becomes powder, and dust is generated in the exhaust gas. For this reason, it is necessary to install a dust collection device for collecting generated activated carbon C dust at the subsequent stage of the moving bed type activated carbon packed tower 40.

On the other hand, in the fixed-bed type activated carbon packed tower 50, the activated carbon C does not move, so that the activated carbon C does not wear out and becomes powder, and it is not necessary to install a dust collector at a later stage. However, the activated carbon C is not continuously renewed as in the moving bed type activated carbon packed tower 40, so that the activated carbon C is gradually deteriorated and the exhaust gas treatment capacity is reduced. Therefore, when the activated carbon C deteriorates, the activated carbon C in the fixed layer 52 must be replaced.

Incidentally, the deterioration of the activated carbon C in the fixed layer 52 is not merely a decrease in the adsorbing ability, but is mainly caused by clogging due to dust flying without being collected by the preceding dust collector. difficult. Therefore, the exchange is not properly performed, and the exchange of the activated carbon C is often performed only when the operation of the entire incinerator, the melting furnace, and the waste treatment facilities is hindered.

The deterioration of the activated carbon C due to clogging is remarkable in the lower portion of the fixed layer 52. Even if clogging occurs in the lower portion of the fixed layer 52, the activated carbon C in the upper portion is not significantly deteriorated. Even though the activated carbon C at the top is sufficiently usable, it is to be replaced all at once. Moreover, when replacing the activated carbon C, it is necessary to take out and treat a large amount of the used activated carbon C that has adsorbed harmful substances such as dioxin at a time.

Furthermore, after the new activated carbon C is filled in the fixed layer 52, it is necessary to level the surface layer by human power in order to make the layer thickness uniform.

[0009]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems in an activated carbon packed tower for treating an exhaust gas of a waste incinerator or a waste melting furnace, in which dust is not generated from the activated carbon packed tower. It is an object of the present invention to provide an activated carbon packed tower which can prevent the occurrence of dust and does not need to install a dust collector at a later stage, and can appropriately and easily exchange activated carbon.

[0010]

According to the present invention, in order to solve the above problems, an activated carbon packed tower provided in an exhaust gas path of a waste treatment facility has an activated carbon inlet at an upper portion and an activated carbon outlet at a lower portion. An activated carbon support bed is provided in the casing, and a detector for detecting the state of deterioration of the activated carbon in the fixed layer formed on the activated carbon support bed is provided.

During operation of the waste treatment facility, the exhaust gas is
After dust is removed by the dust collector, it enters the activated carbon packed tower,
Here, harmful substances such as dioxins in the exhaust gas are adsorbed and removed by the activated carbon. The exhaust gas from which the harmful substances have been removed is discharged from the activated carbon packed tower to the atmosphere through an induction fan and a chimney.

In this activated carbon packed tower, a fixed bed is formed on the activated carbon support bed, and the activated carbon does not move in a gas-flowing state. Therefore, the activated carbon does not wear out and becomes powder, and it is not necessary to install a dust collector at a later stage. Absent. The deterioration state of the activated carbon in the fixed bed is detected by a detector, and when the activated carbon is deteriorated,
The activated carbon is dropped from the activated carbon support floor and stored in the lower part of the casing, and new activated carbon is supplied from the upper activated carbon inlet to form a fixed layer again on the activated carbon support bed. The used activated carbon stored in the lower part of the casing is discharged from the activated carbon outlet.

Since the activated carbon is detected in a deteriorated state by a detector, the activated carbon can be appropriately replaced and does not hinder the operation of the waste disposal equipment. When a plurality of activated carbon support beds are provided in the casing, the thickness of the activated carbon per fixed layer formed on each activated carbon support bed can be reduced. Then, by replacing only the lower activated carbon which is significantly deteriorated due to clogging, the upper undegraded activated carbon can be effectively used.

The activated carbon support floor is made up of a plurality of rotatable mesh floors, so that the exchange of activated carbon is facilitated. If a dispersing device for dispersing the activated carbon supplied into the casing on the activated carbon support floor is provided below the activated carbon input port, the layer thickness on the activated carbon support bed can be made uniform at the time of the activated carbon supply. Therefore, it is not necessary to scrape the surface layer manually to make the layer thickness uniform.

[0015]

FIG. 1 is a configuration diagram of an exhaust gas treatment system of a waste treatment facility provided with an activated carbon packed tower according to an embodiment of the present invention.

A gas cooling tower 4, a dust collecting device 5, an induction fan 6, and a chimney 7 are provided in the exhaust gas path 1 of the waste treatment facility, and the activated carbon is filled between the dust collecting device 5 and the induction fan 6. Tower 8 is installed. An inlet damper 9 and an outlet damper 10 are provided before and after the activated carbon packed tower 8.

The dust collector 5 and the induction fan 6 in the exhaust gas path 1
A bypass duct 2 for exhausting the exhaust gas bypassing the activated carbon packed tower 8 is provided between the bypass duct 2 and the bypass duct 2, and a bypass damper 3 is provided in the bypass duct 2.

The activated carbon packed tower 8 has an activated carbon inlet 12 at an upper part of a casing 11 and an activated carbon outlet 13 at a lower part.
4 are provided. The activated carbon support floor 14 of each stage is constituted by a plurality of rotating mesh floors 15, on which activated carbon C is deposited and a fixed layer 25 is formed.
Are formed. Pressure sensors 30 are provided above and below the lower fixed layer 25 as detectors for detecting the state of deterioration of the activated carbon C in the fixed layer 25.

An activated carbon charging seal valve 16 is provided in the activated carbon charging port 12, and an activated carbon supply conveyor 19 is laid from below the activated carbon supply valve 18 of the activated carbon hopper 17 to above the activated carbon charging seal valve 16. Below the activated carbon inlet 12, a swing flap type dispersion device 20 for dispersing the activated carbon C supplied into the casing 11 on the activated carbon support floor 14 is provided.

The activated carbon discharge port 13 is provided with an activated carbon drawing seal valve 21. Below the activated carbon drawing seal valve 21, an activated carbon transport pipe 23 for pneumatically transporting the used activated carbon C to an incinerator (not shown) by an airflow from a spent activated carbon furnace blower 22 is provided.

During the operation of the waste treatment facility, the exhaust gas discharged from the incinerator is cooled by the gas cooling tower 4 and the dust is removed by the dust collector 5 and then enters the activated carbon packed tower 8 where the waste gas is discharged. Harmful substances such as dioxins are activated carbon C
Is adsorbed and removed. The exhaust gas from which the harmful substances have been removed is discharged from the activated carbon packed tower 8 into the atmosphere through the induction fan 6 and the chimney 7.

In the activated carbon packed tower 8, the pressure sensor 30 detects a pressure loss due to the fixed bed 25 at the lower stage. Fixed layer 25
The deterioration of the activated carbon C is mainly caused by clogging with dust. Therefore, if the pressure loss detected by the pressure sensor 30 exceeds a predetermined value, the activated carbon C is replaced when the incinerator is stopped.

When replacing the activated carbon C, first, the lower mesh floor 15 is rotated to drop the activated carbon C and temporarily store it in the lower portion of the casing 11. Next, the lower mesh floor 15 is returned to a horizontal position, and then the upper mesh floor 15 is rotated to remove the activated carbon C from the lower mesh floor 15.
Supply on top. At this time, by appropriately adjusting the rotation angle of the upper mesh floor 15, the lower support floor 14
The fixed layer 25 having a uniform thickness can be formed thereon.

Then, the upper mesh floor 15 is returned to the horizontal position, the activated carbon charging seal valve 16 is opened, and new activated carbon C supplied from the activated carbon hopper 17 via the activated carbon supply conveyor 19 is supplied to the upper mesh floor 15. At this time, by appropriately adjusting the dispersing device 20, a fixed layer 25 having a uniform thickness can be formed on the upper support floor 14.

The used activated carbon C temporarily stored in the lower portion of the casing 11 is discharged to the activated carbon transport pipe 23 by opening the activated carbon drawing seal valve 21 after the operation of the incinerator is restarted, and is blown into the used activated carbon furnace. The air is transported by air from the blower 22 and blown into the incinerator, where it is burnt and decomposed together with the adsorbed harmful gas components.

As described above, in the activated carbon packed tower 8, since the fixed bed 15 is formed on the activated carbon support bed 14 and the activated carbon C does not move in a gas-flowing state, the activated carbon C does not wear out and becomes powder. There is no need to install a dust collector at a later stage. Deterioration state of activated carbon C in fixed layer 25 is determined by pressure sensor 3
Since it is detected as 0, it can be replaced properly and does not hinder the operation of the waste disposal equipment.

Since the upper and lower activated carbon supporting beds 14 are provided in the casing, the activated carbon C per one layer of the fixed layer 25 formed on each activated carbon supporting floor 14 is provided.
Can be made thinner. Then, only the lower activated carbon C, which is significantly deteriorated due to clogging, is discharged, and the upper undegraded activated carbon C is reused in the lower stage, so that the activated carbon C is effectively used.

Since the activated carbon support floor 14 is composed of a plurality of rotatable mesh floors 15, the activated carbon C can be easily exchanged. The exchange of the activated carbon C is performed in a closed state, and the used activated carbon C having adsorbed harmful substances such as dioxin can be discharged without exposing the activated carbon C to the outside.

Below the activated carbon inlet 12, the casing 1
1 is provided with a dispersing apparatus 20 for dispersing the activated carbon C supplied into the activated carbon support bed 14 on the activated carbon support bed 14. Since the layer thickness on the activated carbon support bed 14 can be made uniform when the activated carbon C is supplied, the activated carbon C is filled with new activated carbon C. Later, it is not necessary to manually scrape the surface layer to make the layer thickness uniform.

It should be noted that a control device for remotely controlling each device such as the mesh floor 15, the activated carbon supply seal valve 16, the activated carbon supply valve 18, the activated carbon supply conveyor 19, the activated carbon drawing seal valve 21, the used activated carbon furnace blower 22, etc. If it is provided so that it can be automatically controlled based on the detection data of the pressure sensor 30, the replacement operation of the activated carbon C can be made easier.

In the casing 11 of the activated carbon packed tower 8, the activated carbon support beds 14 are arranged not only in two stages but also in more stages to increase the fixed layer 25 of the activated carbon C. Activated carbon C can be further effectively used.

In this case, when replacing the activated carbon C, first, the lowermost mesh floor 15 is rotated to drop the activated carbon C, and the activated carbon C is temporarily stored in the lower portion of the casing 11.
Next, the lowermost mesh floor 15 is returned to a horizontal position, and then the uppermost mesh floor 15 is rotated to supply activated carbon C onto the lowermost mesh floor 15. Thereafter, the activated carbon C of the upper stage is sequentially supplied onto the mesh floor 15 of each stage, and finally the new activated carbon C is supplied onto the uppermost mesh floor 15.

FIG. 2 is an explanatory diagram of a case where the fixed bed 25 of the activated carbon C is used in the activated carbon packed tower 8 having the two-stage activated carbon support beds 14. Here, the pressure sensor 3
0 is also arranged on the upper fixed layer 25. A fixed layer 25 of activated carbon C is formed on the lower activated carbon support floor 14, and when the deterioration state is detected by the pressure sensor 30, the lower mesh floor 15 is rotated to drop the activated carbon C and temporarily fall under the casing 11. To store. Then, the activated carbon charging seal valve 16 is opened, new activated carbon C supplied from the activated carbon hopper 17 via the activated carbon supply conveyor 19 is supplied to the upper mesh floor 15, and the fixed layer 25 is placed on the upper activated carbon support floor 14. Form.

The used activated carbon C temporarily stored in the lower part of the casing 11 is discharged to the activated carbon transport pipe 23 by opening the activated carbon drawing seal valve 21 after the operation of the incinerator is restarted, and is blown into the used activated carbon furnace. The air is transported by air from the blower 22 and blown into the incinerator, where it is burnt and decomposed together with the adsorbed harmful gas components.

The operation is performed in this state, and when the deterioration state is detected by the pressure sensor 30, the upper mesh floor 15 is rotated to drop the activated carbon C and temporarily store it in the lower portion of the casing 11. Then, the lower mesh floor 15 is returned to the horizontal position, the activated carbon charging seal valve 16 is opened, and new activated carbon C supplied from the activated carbon hopper 17 via the activated carbon supply conveyor 19 is supplied to the lower mesh floor 15, and the lower activated carbon is supplied. The fixed layer 25 is formed on the support floor 14. Then, by returning the upper mesh floor 15 to a horizontal state, the state returns to the state of FIG.

[0036]

As described above, according to the activated carbon packed tower of the present invention, generation of dust from the activated carbon packed tower can be prevented, so that there is no need to install a dust collector at a later stage, and replacement of the activated carbon can be appropriately performed. Can be done.

When a plurality of activated carbon support beds are provided in the casing, the thickness of the activated carbon per fixed layer formed on each activated carbon support bed can be reduced, and deterioration due to clogging can be prevented. By replacing only the significant lower activated carbon, the upper undegraded activated carbon can be effectively used.

When the activated carbon support floor is constituted by a plurality of rotatable mesh floors, the exchange of activated carbon becomes easy. If a dispersing device for dispersing the activated carbon supplied into the casing on the activated carbon support floor is provided below the activated carbon input port, the layer thickness on the activated carbon support bed can be made uniform at the time of the activated carbon supply. Therefore, it is not necessary to scrape the surface layer manually to make the layer thickness uniform.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an exhaust gas treatment system of a waste treatment facility provided with an activated carbon packed tower according to an embodiment of the present invention.

FIG. 2 is an activated carbon packed column equipped with a two-stage activated carbon support bed,
It is explanatory drawing at the time of using the fixed layer of activated carbon in one layer.

FIG. 3 is an explanatory view of a configuration of a conventional moving bed type activated carbon packed tower.

FIG. 4 is an explanatory view of a configuration of a conventional fixed-bed activated carbon packed tower.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Exhaust gas path 2 Bypass duct 3 Bypass damper 4 Gas cooling tower 5 Dust collector 6 Induction fan 7 Chimney 8 Activated carbon filling tower 9 Inlet damper 10 Outlet damper 11 Casing 12 Activated carbon inlet 13 Activated carbon outlet 14 Activated carbon support floor 15 Mesh floor 16 Activated carbon injection seal valve 17 Activated carbon hopper 18 Activated carbon supply valve 19 Activated carbon supply conveyor 20 Dispersing device 21 Activated carbon extraction seal valve 22 Spent activated carbon furnace blower 23 Activated carbon transport pipe 25 Fixed layer 30 Pressure sensor C Activated carbon

[Procedure amendment]

[Submission date] July 8, 1998 (1998.7.8)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claim 4

[Correction method] Change

[Correction contents]

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) CE01 CE02 CF02 CF03 CG01 CH01 CK07

Claims (4)

[Claims] 1. An activated carbon packed tower provided in an exhaust gas path of a waste treatment facility, wherein an activated carbon support bed is provided in a casing having an activated carbon inlet at an upper portion and an activated carbon outlet at a lower portion. An activated carbon packed tower provided with a detector for detecting a state of deterioration of activated carbon in a fixed bed formed on a floor. 2. The activated carbon packed column according to claim 1, wherein a plurality of activated carbon support beds are provided in the casing. 3. The activated carbon packed column according to claim 1, wherein the activated carbon support bed is constituted by a plurality of rotatable mesh floors. 4. A dispersion apparatus for dispersing activated carbon supplied into a casing on an activated carbon support bed below an activated carbon inlet. Activated carbon packed tower.