JPH04891Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to an exhaust gas treatment device for treating highly dust-containing exhaust gas discharged from an incinerator or the like.

[Prior art] Conventionally, an exhaust gas treatment device removes dust and harmful gases from the exhaust gas by installing louvers, screens, etc. facing each other in the exhaust gas passage, and filling the gap with a carrier to form a moving packed moving bed. It has been known. As shown in FIG. 6, this exhaust gas treatment device has screens 3 and 4 provided facing each other in a casing 2 forming an exhaust gas passage 1.
An upper hopper 5 for supplying the carrier is provided above the hopper 5,
A lower hopper 6 is provided in the lower part separated from the exhaust gas passage 1, and a lower hopper 6 is provided in the lower hopper 6 for closing the space between the screens 3 and 4 and for discharging the carriers in the filling moving bed 7 between the screens 3 and 4 to the hopper 6. It is configured by providing a rotor 8.

In this exhaust gas treatment device, harmful gases in the exhaust gas are removed by reacting with the carrier of the packed moving bed 7, and dust and the like are also captured by the carrier and removed.

[Problems to be solved by the invention] However, when treating high-particulate exhaust gas, dust etc. in the exhaust gas falls and accumulates inside the upstream casing 2 before passing through the front screen 3, and in rare cases, the dust etc. in the exhaust gas falls and accumulates in the upstream casing 2. Dust and the like that are not captured by the moving layer 7 even after passing through the rear screen 4 fall and accumulate on the downstream casing 2 through the rear screen 4 . When dust etc. accumulates at the bottom of the casing 2 in this way, it cannot be taken out, and when the amount of accumulated dust increases, it blocks the screens 3 and 4, preventing exhaust gas from flowing into the moving layer 7 in that area, and harmful gas There is a problem that the removal rate becomes worse.

The present invention has been made in consideration of the above-mentioned circumstances, and an object of the present invention is to provide an exhaust gas treatment device that can take out dust and the like even if it falls and accumulates before and after the packed moving bed.

[Means and effects for solving the problems] In order to achieve the above object, the present invention provides front and rear louvers facing each other in the exhaust gas passage to form a carrier-filled moving layer, and a gap between the louvers. In an exhaust gas treatment device equipped with a rotor that closes the lower part of the hopper and discharges the carriers in the moving layer into the hopper, the lower surface of the upstream exhaust gas passage is sloped to move accumulated dust, etc. to the lower part. On the other hand, the lower surface of the downstream exhaust gas passage is sloped so as to be continuous with the lowest louver.
The lower surfaces of the exhaust gas passages of the front and rear louvers are inclined toward the louver side, and the upstream side, where there is a large amount of accumulation, allows dust to be introduced directly into the rotor casing, and the downstream side, where there is a relatively small amount of accumulation, is arranged so that the lower side By introducing the material into the packed moving bed through the louver and recovering it, the accumulation of dust and the like is prevented and the filling moving bed is prevented from being blocked by the dust and the like.

[Embodiment] Hereinafter, a preferred embodiment of the exhaust gas treatment device according to the present invention will be described based on the accompanying drawings.

1 to 3, reference numeral 10 denotes a main body casing forming an exhaust gas passage 11, and an inlet 12 and an outlet 13 for introducing and discharging exhaust gas are provided before and after the main casing.

A packed moving bed 15 is formed in the main casing 10, which is composed of granular carriers 14 that move in the direction of gravity so as to be transverse to the flow of exhaust gas.

The filled moving bed 15 is provided with a front louver 16 on the upstream side with respect to the exhaust gas passage 11, and a rear louver 17 on the downstream side, and a granular carrier 14 such as silica sand, lime, slag, cement clay, etc. is placed between them. Filled and formed.

The front and rear louvers 16 and 17 are provided at a predetermined interval along the vertical direction of the main body casing 10, and are provided such that the vertical positions of the front louver 16 and the rear louver 17 are shifted from each other. Further, each of the louvers 16 and 17 is inclined downward toward the center of the moving layer 15, and is provided so that the front and rear louvers 16 and 17 are close to each other.

An introduction port 18 for supplying the carrier 14 between the front and rear louvers 16 and 17 is formed in the upper part of the main body casing 10, and the louvers 16 and 17 are provided in the lower part.
A rotor 20 is provided for discharging the carriers 14 that have descended through the rotor casing 17 into the lower rotor casing 19.

This rotor casing 19 is formed integrally with the main body casing 10, and its upper part is open and the upstream lower surface 10a and downstream lower surface 10b of the main body casing 10 are connected to the rotor casing 1.
It is formed so as to be inclined downward toward 9.

A gap 21 is formed between the upstream side of the rotor casing 19 and the rotor 20, and communicates with the upstream exhaust gas passage 11. Further, the lower downstream surface 10a of the main body casing 10 and the lowermost downstream louver 17a are integrally and continuously formed, and the upper downstream side of the rotor casing 19 is closed.

A screw conveyor 22 for transporting and discharging the carriers 14 discharged from the rotor 20 is provided at the bottom of the rotor casing 19, and a double flap damper 23 is provided at the discharge port of the screw conveyor 22.
A classifier 24 is connected to the classifier 24 via, etc. This classifier 24 is connected to a vertical conveyor 2 such as a bucket elevator.
5 are connected to each other, and the granular carrier 14 after dust etc. has been separated by the classifier 24 is circulated to the inlet 18 at the upper part of the main body casing 10 via the vertical conveyor 25.

The front and rear louvers 16, 17 have an inclination α of around 60 degrees, as shown in FIG.
The distance L between the upper and lower louvers 16 and 17 is approximately 100 mm.
The distance d between the tips of the front and rear louvers 16 and 17 is -5
By keeping the distance within the range of approximately 25 mm to 25 mm, dust can be captured well, and a moving layer 14 with little pressure loss can be formed even when the gas velocity is around 0.6 m/sec.

Next, the operation of this embodiment will be explained.

When the exhaust gas is introduced into the exhaust gas passage 11 from the inlet 12 of the main casing 10, the front louver 1
6 and flows into the packed moving bed 15, where dust and the like are captured by the granular carriers 14 that descend within the moving bed 15, and hydrogen chloride, sulfur oxides, etc. in the exhaust gas are trapped by the carriers 14. Reacts with lime powder and is removed. In this way, the packed moving bed 15
The exhaust gas from which dust and harmful gases have been removed flows from the rear louver 17 to the downstream exhaust gas passage 11 and is discharged from the outlet 13.

By adjusting the rotational speed of the rotor 20 below the filled moving bed 15, the descending speed of the carriers 14 within the moving bed 15 can be adjusted.

The carrier 14 discharged into the rotor casing 19 by the rotor 20 is transferred from the screw conveyor 22 to the classifier 2 via the double flap damper 23.
4, where dust and the like are removed, and circulated to the inlet 18 by a vertical conveyor 25.

In this exhaust gas treatment, if the exhaust gas is high in particulate content, for example, if lime powder or the like is blown into the exhaust gas to remove harmful gases such as hydrogen chloride, on the upstream side of the exhaust gas passage 11, the front Before reaching the louver 15, some of the dust in the exhaust gas falls and accumulates on the upstream lower surface 10a of the main casing 10, but due to the slope of the lower surface 10a, the dust falls due to gravity and fills the gap 21 between the rotor casing 19 and the rotor 20. carriers 1 from the packed moving bed 15 are introduced into the rotor casing 19 through
It is discharged together with 4. Moreover, in this gap 21,
Exhaust gas also flows in, but roller casing 1
The downstream side of the rotor 9 and the rotor 20 are partitioned by the lowest louver 17a and the downstream lower surface 10b.
Exhaust gas does not flow into the downstream side.

Further, as described above, the high dust content exhaust gas flows from the front louver 16 into the packed moving bed 14, and after removing dust and harmful gases, it flows from the rear louver 17 to the downstream exhaust gas passage 11, where it is transferred into the exhaust gas. Dust that was not captured by the layer 14 is mixed in,
This falls and accumulates on the lower surface 10b of the downstream passage 11. This dust moves in the vertical force direction along the slope of the lower surface 10b, and flows into the filling moving layer 15 through between the lowermost louver 17a and the upper louver 17, as shown in FIG. , will be collected. The amount of dust that accumulates on the downstream side is smaller than that on the upstream side, and even if the dust passes between the louvers 17, the louvers 17 will not be blocked.

In this way, the dust and the like that fall and accumulate in the exhaust gas passages 11 on the upstream and downstream sides of the filled moving bed 14 can be collected into the rotor casing 19, so that the louvers 16 and 17 are not clogged.

FIG. 4 shows another embodiment of the present invention,
An electrostatic precipitator 26 is provided on the downstream side of the main casing 10.
are provided consecutively.

As shown in FIG. 4, the electrostatic precipitator 26 includes a plurality of dust collecting plates 27 arranged parallel to the exhaust gas flow inside the main body casing 10, and a large number of them arranged between the dust collecting plates 27. It consists of a linear discharge electrode 28.

The main body casing 10 has a collection port 29 below the dust collection plate 27 for appropriately collecting collected dust.
, and an outlet 13 is formed downstream of the dust collector 26 .

In this example, the dust that falls and accumulates on the upstream side of the filled moving bed 15 is collected into the rotor casing 19 from the lower surface 10a, but the dust on the downstream side is mainly collected by the electrostatic precipitator 26. . Furthermore, the dust that falls and accumulates on the lower surface 10b of the main body casing 10 on the downstream side of the filled moving bed 15 before entering the dust collector 26 is collected into the moving bed 15 through the louvers 17 as explained in FIG. Ru.

Normally, the gas velocity of the electrostatic precipitator 26 is 0.4~
0.6 m/sec, but by bringing the front and rear louvers 16 and 17 close to each other as described above, the gas velocity is three times that of the conventional moving bed gas velocity of 0.2 m/sec, and the electrostatic precipitator 26 The exhaust gas can be caused to flow into the packed moving bed 15 at the same speed as the gas speed of
Moreover, pressure loss can be reduced.

FIG. 5 shows still another embodiment of the present invention, and shows an example in which the exhaust gas treatment device A of the present invention is incorporated into the exhaust gas treatment device of an incinerator.

In FIG. 5, 30 is an incinerator such as a fluidized bed, and a gas cooling device 31 is connected to its exhaust gas outlet, and the exhaust gas treatment device A explained in FIG. The chimney 3 is connected to the chimney 26 through the induced blower 33.
4 are connected to form a garbage incineration plant.

A duct 32 leading from the gas cooling device 31 to the exhaust gas treatment device A is supplied with lime powder for injecting lime powder such as slaked lime (Ca(OH) ₂ ) or quicklime (CaO) into the exhaust gas passing through the duct 32. Device 35 is connected.

This lime powder supply device 35 includes a hopper 36 that discharges lime powder, and a blower 37 that supplies conveying air.
and a conveying line 38 connected to the duct 32.

In the above, combustion exhaust gas containing harmful gases such as hydrogen chloride and SOx is exhausted from the incinerator 30 due to thermal decomposition of PVC plastics contained in the incinerated material, and the heat amount is recovered by the gas cooling device 31. After that, it flows into the duct 32.

Lime powder is blown into the duct 32 from a lime powder supply device 35, and this lime powder reacts with hydrogen chloride in the exhaust gas to become calcium chloride and remove the hydrogen chloride. In the case of SOx, lime powder turns into calcium sulfate and removes SOx.

The exhaust gas into which this lime powder has been blown is introduced into the exhaust gas treatment device A of the present invention, where harmful gases and dust such as lime powder are removed, and then flowed to the electrostatic precipitator 26 where the dust in the exhaust gas is removed. It is then discharged from the chimney 34.

[Effects of the Invention] As is clear from the above explanation, the present invention provides the following excellent effects.

Dust that falls and accumulates when exhaust gas passes before and after the packed moving bed formed by the front and rear louvers is collected in the rotor casing below the packed moving bed, eliminating the problem of clogging the louvers.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing one embodiment of the present invention;
The figure is an enlarged sectional view of the main part of Figure 1, Figure 3 is a diagram explaining the front and rear louvers of Figure 1, Figure 4 is a diagram showing another embodiment of the present invention, and Figure 5 is an incinerator. FIG. 6 is a diagram showing an example to which the present invention is applied, and FIG. 6 is a diagram showing a conventional example. In the figure, 10 is a main body casing, 11 is an exhaust gas passage, 14 is a carrier, 15 is a packed moving bed, 16, 17
is a louver, 19 is a rotor casing, and 20 is a rotor.

Claims (1)

[Scope of utility model registration request] An exhaust gas treatment device that has front and rear louvers facing each other in an exhaust gas passage to form a moving bed filled with carriers, and a rotor that closes the lower part between the louvers and discharges the carriers in the moving bed into the hopper. In this case, the lower surface of the upstream exhaust gas passage is formed to be inclined to move accumulated dust etc. to the lower part, and the lower surface of the downstream exhaust gas passage is formed to be inclined so as to be continuous with the lowermost louver. ,
An exhaust gas treatment device characterized by discharging accumulated dust from both the upstream side and the downstream side to the bottom together with a carrier to prevent clogging of a louver portion.