JP2003126651A - Exhaust gas treatment apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a exhaust gas treatment apparatus capable of efficiently detecting of hot spots. SOLUTION: The exhaust gas treatment apparatus is provided with temperature measuring means 50 for measuring the temperature of the inside of a tower 2 in a portion lower than a gas feeding part 32a and a gas discharge part 31a where hot spots are easily formed in an adsorption tower 11. Accordingly, the apparatus is enabled to efficiently and quickly detect hot spots.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an exhaust gas treating apparatus for desulfurizing exhaust gas.

[0002]

2. Description of the Related Art Conventionally, a carbonaceous adsorbent such as activated carbon is caused to flow horizontally to a moving bed in which a carbonaceous adsorbent moves downward, and sulfur components such as SO _{x in} the exhaust gas are adsorbed and removed by the carbonaceous adsorbent. Exhaust gas treatment devices are known. In such an exhaust gas treatment apparatus, a hot spot may be generated in the moving bed due to the heat of adsorption generated during the adsorption of sulfur and the like. Then, if such a hot spot is left, the carbonaceous adsorbent is gradually ignited and burned,
The temperature of the carbonaceous adsorbent suddenly rises to deteriorate the adsorption efficiency and the like, and the carbonaceous adsorbent is burned, so that the desulfurization treatment cannot be performed efficiently.

Therefore, in the conventional exhaust gas treatment equipment, in order to detect the occurrence of hot spots, the temperature near the center of the portion of the moving bed that comes into contact with the exhaust gas is measured, or the CO concentration of the treated gas is measured. It was.

[0004]

However, the conventional exhaust gas treating apparatus has a problem in that the occurrence of the hot spot cannot be sufficiently detected. That is, in the measurement with the thermometer, the portion where the hot spot occurs is not necessarily near the center of the moving layer, so that it cannot be detected efficiently, but also in the measurement of the CO concentration, the CO concentration increasing due to the formation of the hot spot is about 1000 PPM. However, the accuracy of detection is very poor in exhaust gas containing CO in advance such as combustion exhaust gas.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an exhaust gas treatment apparatus capable of efficiently detecting the occurrence of hot spots.

[0006]

As a result of intensive studies, the present inventor has found that in such an exhaust gas treatment apparatus, hot spots are mainly carbonaceous adsorbents that move downward, and the carbonaceous adsorbents. Exhaust gas traversing the, the contact with is insufficient, the place where the cooling of the carbonaceous adsorbent by the gas flow is not sufficient, especially found to occur below the gas introduction opening and the gas discharge opening, The present invention has been completed.

That is, in the exhaust gas treating apparatus of the present invention, the gas introduction opening for introducing the exhaust gas and the gas discharge opening for discharging the exhaust gas are formed on the side surface, and the carbonaceous adsorbent for adsorbing the sulfur content in the exhaust gas is provided. A column that is supplied from the upper part to the inside and that discharges the carbonaceous adsorbent from the lower part; and a temperature measuring unit that measures the temperature in the column below the gas introduction opening and the gas discharge opening. Characterize.

According to the exhaust gas treating apparatus of the present invention, it is possible to measure the temperature in the tower below the gas inlet opening and the gas outlet opening where hot spots tend to occur, so that hot spots occur. In this case, this can be detected immediately and efficiently.

Here, it is preferable to further include a temperature measuring means for measuring the temperature in the tower above the gas introduction opening and the gas discharge opening.

There is almost no gas flow above the gas introduction opening and the gas discharge opening, and hot spots may occur. By providing such temperature measuring means, hot spots can be prevented. Further, it is possible to surely detect.

Further, there is provided a partition wall that extends from the side surface on the gas inlet opening side to the side surface on the gas outlet opening side in the tower and divides the space in the tower horizontally, and the temperature measuring means has a rod shape. It is preferable that a plurality of temperature detection units are provided in the length direction while being installed so as to penetrate the partition wall and respectively correspond to the divided spaces.

Thus, when partition walls are installed in the tower for the reason that the flow of the carbonaceous adsorbent is close to the piston flow, etc., the above-mentioned locations in each space (rather than the gas introduction opening and the gas discharge opening) Temperatures (below and above) can be easily measured, and temperature measuring means can be easily installed.

[0013]

DETAILED DESCRIPTION OF THE INVENTION Referring to the accompanying drawings,
A preferred embodiment of the exhaust gas treating apparatus according to the present invention will be described in detail. In the description of the drawings, the same or corresponding elements will be denoted by the same reference symbols, without redundant description.

FIG. 1 is a schematic diagram showing an exhaust gas treatment system 100 according to this embodiment. In the exhaust gas treatment system 100 of the present embodiment, a downward moving layer of a carbonaceous adsorbent such as activated carbon is formed in the adsorption tower (exhaust gas treating apparatus) 11, and SO _{x is applied to} the moving layer of the carbonaceous adsorbent.
Exhaust gas containing sulfur content such as is horizontally supplied through the booster fan 20 and ammonia gas is supplied to this exhaust gas by the ammonia supplier 25, and the sulfur content in the exhaust gas is supplied to the carbonaceous adsorbent as sulfuric acid or ammonium sulfate salt. The exhaust gas desulfurized after being adsorbed and removed in a shape and discharged from the chimney 40 is configured.

Further, the exhaust gas treatment system 100 is
The carbonaceous adsorbent having adsorbed sulfur content is extracted from the bottom of the adsorption tower 11 by the bucket conveyor 22 and supplied to the desorption tower 61 from above via the rotary valve 62, and the heating gas generated in the hot stove 65 is blown by the blower 66. Desorption tower 6
It is supplied to the heat exchanger in 1 to heat the carbonaceous adsorbent, desorb the adsorbed sulfur content and reactivate the carbonaceous adsorbent, and from the desorbed sulfur content, by-products such as sulfuric acid and sulfur are produced. The regenerated carbonaceous adsorbent collected from the bottom through the rotary valve 63 while being recovered by the recovery device 70 is sieved by a sieving machine 64 to select a carbonaceous adsorbent having a particle size of a predetermined value or more and to bucket. While returning to the upper part of the adsorption tower 11 via the conveyor 23,
The carbonaceous adsorbent having a particle size smaller than a predetermined value is discharged as dust.

As shown in FIGS. 2 and 3, the adsorption tower 11 has a rectangular tubular outer wall 41 installed in the vertical direction, and exhaust gas is introduced into the outer wall 41 at the lower center of one side surface 41a of the outer wall 41. The gas inlet nozzle 48 for introducing is provided. Inside the outer wall 41, the gas inlet nozzle 48 extends from the side surface 41a to the side surface 41c opposite to the side surface 41a, and stands up and down so as to sandwich the opening formed in the side surface 41a by the gas inlet nozzle 48. A pair of rectangular louver inlet plates 32, 32 that are provided and through which exhaust gas can pass
Is equipped with.

As shown in FIG. 3, the louver inlet plate 32 except for the upper end and the lower end is an opening provided with louver blades so that the exhaust gas can pass and the carbonaceous adsorbent cannot pass. A certain louver inlet (gas introduction opening)
32a.

Further, the adsorption tower 11 is horizontally arranged between a portion of the louver inlet plate 32 below the louver inlet portion 32a and a portion of the other louver inlet plate 32 below the louver inlet portion 32a. A central lower lid 42 that extends and prevents downward flow of exhaust gas is provided, and a portion above the louver inlet portion 32a of one louver inlet plate 32 and a louver inlet portion 32a of the other louver inlet plate 32 are provided.
A central upper lid 46 that extends horizontally between the upper portion and the upper portion and that prevents the exhaust gas from flowing upward is provided.

The louver inlet plates 32, 32, the side surfaces 41a, 41c of the outer wall 41, the central lower lid 42 and the central upper lid 46 define an exhaust gas distribution region 101, and as shown in FIGS. 11 is a gas inlet nozzle 4
The exhaust gas introduced into the exhaust gas distribution area 101 via 8 is distributed in both directions of the louver inlet plate 32 and passed through each louver inlet plate 32.

The adsorption tower 11 has a louver inlet plate 32.
Between the louver inlet plate 32 and the side face 41b of the outer wall 41 that vertically covers the end face of the side face 41a and extends from the side face 41a to the side face 41c. Louver outlet (gas discharge opening) that allows gas to pass but not carbonaceous adsorbent
Each is provided with a louver outlet plate 31 having 31a.
Then, the exhaust gas that has passed through the louver inlet portion 32a receives the louver outlet portion 31 facing the louver inlet portion 32a.
Pass a toward the side surface 41b side of the outer wall 41.

Further, the adsorption tower 11 is, as shown in FIG.
Installed on the upper end of the louver outlet plates 31, 31 and on the upper ends of the side faces 41a, 41c sandwiched between the louver outlet plates 31, 31, and an inlet guide 44 closed upward and the upper end of the inlet guide 44. And a rotary valve 12 that is connected to the bucket conveyor 23 and controls the inflow of the carbonaceous adsorbent.

At the upper ends of the louver inlet plates 32, 32, a carbon-like adsorbent supplied from above is introduced between the louver inlet plate 32 and the louver outlet plate 31, respectively. Are connected.

The lower ends of the louver inlet plate 32 and the louver outlet plate 31 facing each other are closed downward so as to receive the carbonaceous adsorbent supplied between the louver inlet plate 32 and the louver outlet plate 31. The hopper members 36 are connected to each other, and the lower ends of the hopper members 36 are provided with roll feeders 37 that can discharge the carbonaceous adsorbent from the hopper member 36 downward by a predetermined amount.
The side surface 4 of the inlet guide 44, the louver inlet plate 32, the louver outlet plate 31, the hopper member 36, and the outer wall 41.
The moving bed region 102 is defined by 1a and 41c, and these constitute the adsorption section (tower) 2.

In the moving bed region 102, a plurality of plates perpendicular to the louver inlet plate 32 and the louver exit plate 31 are provided to partition the moving bed region 102 in the horizontal direction.
4 are separated by a predetermined distance. This partition 34
In addition to the purpose of flowing the carbonaceous adsorbent that moves downward in the moving bed region 102 with a piston flow without stagnation, and the purpose of preventing the spread of fire in the horizontal direction when ignition / combustion of the carbonaceous adsorbent occurs. The louver inlet plate 32 and the louver outlet plate 31 are installed for the purpose of reinforcement.

The adsorption tower 11 has a louver outlet plate 31.
Each of the louver outlet portions of the louver outlet plate 31 is provided with a horizontal lower lid 43 that horizontally extends between a portion below the louver outlet portion 31a and the side surface 41b and that prevents exhaust gas from flowing downward. Part above 31a and side 41b
And a horizontal upper lid 47 that extends in the horizontal direction and that prevents the exhaust gas from flowing upward. And the outer wall 4
1 side surfaces 41a, 41b, 41c, louver outlet plate 3
1, the lateral lower lid 43 and the lateral upper lid 47 define the outer discharge region 103 into which the exhaust gas passing through the louver outlet 31a is introduced.

Further, in the outer discharge area 103, as shown in FIG.
As shown in FIG. 3 and FIG. 3, gas outlet nozzles 49 for collecting the gas led to each outer discharge area 103 and discharging the collected gas to the outside are connected.

Further, as shown in FIG. 3, the adsorption tower 11 is closed at the lower end of the outer wall 41 toward the bottom, and an outlet guide 45 for storing the carbonaceous adsorbents discharged from the roll feeder 37 of the adsorbing section 2 is stored. And a rotary valve 13 installed at the lower end of the outlet guide 45 and connected to the bucket conveyor 22 for adjusting the discharge amount of the carbonaceous adsorbent.
And are equipped with.

In the adsorption tower 11 in the exhaust gas treatment system 100 of this embodiment, the louver inlet plate 32 has a portion below the louver inlet portion 32a, and the louver outlet plate 3 is provided.
A thermocouple (temperature measuring means) 50 for measuring the temperature of a space sandwiched between the louver outlet 31a and a portion below the louver outlet 31a. The thermocouple 50 has a rod-like shape and is horizontally installed by penetrating the partition walls 34 from the outside of the side surface 41 a of the outer wall 41 and measuring the temperature of each space partitioned by the partition walls 34. A plurality of 51 are installed in the length direction to detect hot spots.

The adsorption tower 11 has a louver inlet plate 32.
Of the rod-shaped thermocouple (similar to the thermocouple 50) for measuring the temperature of the space sandwiched between the portion above the louver inlet 32a and the portion above the louver outlet 31a of the louver outlet plate 31. Temperature measuring means) 52.

Further, in the exhaust gas treatment system 100 of this embodiment, when a hot spot occurs on the carbonaceous adsorbent, the temperature rise of the hot spot is suppressed in order to suppress the temperature rise of the hot spot.
As shown in FIG. ₃ , a nitrogen line L1 for supplying N ₂ into the adsorption tower 11, a valve 6 for adjusting the flow rate of the nitrogen line L1, a thermocouple 52 and a thermocouple 50 are connected to each other, and the thermocouple 50, The temperature monitoring device 5 controls the valve 6 to supply N ₂ into the adsorption tower 11 on the assumption that a hot spot occurs when the temperature of 52 exceeds a predetermined reference value.

Next, the operation of the exhaust gas treatment system 100 according to this embodiment will be described.

First, the carbonaceous adsorbent transferred by the bucket conveyor 23 is charged into the adsorption section 2 in the adsorption tower 11 via the rotary valve 12, and the carbonaceous adsorbent inside the adsorption section 2 is fed by the roll feeder 37. A certain amount of the carbonaceous adsorbent is discharged through the adsorbent 2 to form a downward moving layer of the carbonaceous adsorbent.

On the other hand, the exhaust gas is introduced into the adsorption tower 11 through the booster 20 and the gas inlet nozzle 48, and
Ammonia gas is supplied to the exhaust gas by the ammonia supply device 25.

The exhaust gas introduced from the gas inlet nozzle 48 reaches the exhaust gas distribution region 101, and the flow is separated into two, and the moving layer region of the adsorption unit 2 passes through the louver inlet portion 32a of the louver inlet plate 32. Each is introduced into 102 and contacts a moving bed of carbonaceous adsorbent moving downward.

At this time, the sulfur content such as SO _{x in} the exhaust gas is adsorbed on the carbonaceous material in the form of sulfuric acid produced by reacting with the moisture in the exhaust gas or in the form of ammonium sulfate salt produced by the reaction of this sulfuric acid with ammonia. Adsorbed on the material. Note that in the moving bed of the carbonaceous adsorbent, if it contains NO _x in the exhaust gas NO _x is reduced by reacting with ammonia to N ₂ by the catalytic action of the carbonaceous adsorbent, in the exhaust gas When the dioxin is contained, the dioxin is adsorbed by the carbonaceous adsorbent, and when the exhaust gas contains particles such as soot and dust, the particles are filtered and collected by the moving bed of the carbonaceous adsorbent.

Then, the treated gas which has been subjected to such a treatment is supplied to the louver outlet 31a of the louver outlet plate 31.
Through the gas outlet nozzle 49 and the chimney 40, and is discharged into the atmosphere.

On the other hand, the carbonaceous adsorbent that has adsorbed the sulfur content is introduced into the desorption tower 61, and the combustion gas from the hot stove 65 is used for 40 times.
When heated to about 0 ° C, the sulfur content is desorbed as SO _{x and the} like, the carbonaceous adsorbent is reactivated, and the desorbed sulfur content is oxidized or reduced by the by-product recovery device 70 to produce sulfuric acid or simple substance. While recovering sulfur and the like, the reactivated carbonaceous adsorbent is introduced into the sieving machine 64, fine powder is removed as dust, and then returned to the adsorption tower 11 via the rotary valve 12.

In such an exhaust gas treatment, in the adsorption tower 11, the heat of adsorption that is generated when the carbonaceous adsorbent adsorbs the sulfur and the like, and the heat that is taken away from the carbonaceous adsorbent by the flow of the exhaust gas, Balance, and the temperature of the carbonaceous adsorbent constituting the moving bed is maintained at about 100 to 150 ° C, which is a preferable temperature for adsorbing sulfur, etc. The speed etc. are set.

However, when the operation of the exhaust gas treatment system 100 is continued, in particular, the portion where the flow of the exhaust gas across the moving bed of the carbonaceous adsorbent in the horizontal direction becomes insufficient, that is, the louver inlet plate. A hot spot often occurs in a space sandwiched between a portion of the louver outlet plate 32 below the louver inlet portion 32a and a portion of the louver outlet plate 31 below the louver outlet portion 31a.

Here, in the adsorption tower 11 according to the exhaust gas treatment system 100 of the present embodiment, the louver inlet plate 3
The temperature is measured by the thermocouple 50 in the space sandwiched between the portion below the louver inlet 32a and the portion below the louver outlet 31a of the louver outlet plate 31. The occurrence of hot spots is detected quickly and efficiently. Therefore, before the hot spot or the carbonaceous adsorbent in the vicinity thereof is ignited, burned, or spread, the temperature monitoring device 5 prevents N _{2 from} entering the adsorption tower 11 in order to suppress the temperature rise of the hot spot. Measures such as blowing of active gas are taken, and the exhaust gas is treated safely and efficiently.

Also, in the present embodiment, similarly, the gas flow is insufficient and hot spots are likely to occur, and the portion above the louver inlet portion 32a of the louver inlet plate 32 and the louver outlet portion of the louver outlet plate 31. Since the thermocouple 52 for measuring the temperature is provided also in the space sandwiched between the portion above 31a, the occurrence of the hot spot can be detected more reliably.

Further, in this embodiment, since a so-called hybrid type thermocouple having a plurality of measuring terminals in the length direction is used, each of the adsorption towers 11 partitioned by the partition wall 34 into a plurality of regions is used. The temperature of the adsorption unit 2 can be easily and suitably measured and installed easily.

The exhaust gas treating apparatus according to the present invention is not limited to the above-mentioned embodiment, but can take various modifications.

For example, in this embodiment, the louver inlet 32a and the louver outlet 31a, which are openings having louver blades, are used as the gas inlet opening and the gas outlet opening of the adsorption unit 2, but carbon is used. It suffices that the exhaust gas can pass through while the quality adsorbent is kept inside, and for example, an opening formed by a mesh or the like may be used.

Further, in the present embodiment, the moving layer made of the carbonaceous adsorbent is formed in the adsorbing section 2, but the present invention is not limited to this, and it may be used as a fixed layer or by intermittently moving the carbonaceous adsorbent. A moving layer may be formed.

Further, the present apparatus can treat various exhaust gases such as sintering exhaust gas, boiler exhaust gas, waste incinerator exhaust gas, RDF exhaust gas, semiconductor manufacturing equipment exhaust gas, vehicle exhaust gas and the like.

[0047]

EFFECT OF THE INVENTION Since the exhaust gas treating apparatus of the present invention is equipped with the temperature measuring means for measuring the temperature in the column below the gas inlet opening and the gas outlet opening where hot spots are likely to occur, the hot spot It is possible to detect the occurrence quickly and efficiently. Therefore, before the hot spot or the carbonaceous adsorbent near it is ignited, burned, or spread, take measures such as injecting an inert gas into the adsorption tower to suppress the temperature rise of the hot spot. Therefore, the exhaust gas can be treated safely and efficiently.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an exhaust gas treatment system of the present embodiment.

FIG. 2 is a horizontal sectional view of the adsorption tower in FIG.

FIG. 3 is a partially cutaway perspective view of the adsorption tower in FIG.

[Explanation of symbols]

2 ... Adsorption part (tower), 11 ... Adsorption tower (exhaust gas treatment device),
31a ... Louver outlet (gas discharge opening), 32a ...
Louver inlet (gas introduction opening), 34 ... Partition wall, 5
0,52 ... Thermocouple (temperature measuring means), 51 ... Temperature detection part, 100 ... Exhaust gas treatment system.

Claims (3)

[Claims] 1. A gas inlet opening for introducing exhaust gas and a gas outlet opening for exhausting the exhaust gas are formed on side surfaces,
A carbonaceous adsorbent that adsorbs the sulfur content in the exhaust gas is supplied from the upper part to the inside and a tower that discharges the carbonaceous adsorbent from the lower part, and the gas introduction opening and the gas discharge opening below the gas discharge opening. An exhaust gas treatment apparatus comprising: a temperature measuring unit that measures a temperature in the tower. 2. The exhaust gas treating apparatus according to claim 1, further comprising temperature measuring means for measuring a temperature in the tower above the gas introduction opening and the gas discharge opening. 3. A partition wall extending in the tower from a side surface on the gas inlet opening side to a side surface on the gas outlet opening side to divide a space in the tower in a horizontal direction, the temperature measuring means And a plurality of temperature detectors each having a rod shape and penetrating through the partition wall and corresponding to the divided spaces in the length direction thereof.
Or the exhaust gas treatment device according to 2.