JPH04293516A - Exhaust gas treatment apparatus - Google Patents

Abstract

PURPOSE:To slow down the lowering rate of the adsorbing ability of an adsorbing material by a method wherein a purified gas is sent back into the exhaust gas being sent from an exhaust gas conduit pipe into an adsorption tower instead of being discharged from a purified gas discharge pipe into the atmospheric air to supply the flow of exhaust gas into the adsorption tower in a constant amt. CONSTITUTION:An exhaust gas treatment apparatus which comprises an adsorption tower 11 packed with an adsorption material 52 and adapted to receive therein exhaust gas from an exhaust gas conduit pipe 12; a purified gas discharge pipe 13 for discharging therethrough a purified gas produced by treating the exhaust gas with the adsorbing material 52 in the adsorption tower 11 ; an emergency exhaust gas discharge pipe 14 provided with a discharge pipe adjusting valve 15 for freely adjusting a pipe in communication with the exhaust gas conduit pipe 12 from an opened and a closed state; a purified gas circulating pipe 31 provided for keeping the exhaust gas conduit pipe 12 and the purified gas discharge pipe 13 in communication with each other; and a circulating means 32 for sending back the purified gas passing through the purified gas discharge pipe 13 into the exhaust gas conduit pipe 12, whereby the lowering rate of the adsorbing ability of the adsorbing material can be slowed down.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention consists of an adsorption tower body containing an adsorbent, an exhaust gas introduction pipe for introducing exhaust gas into the adsorption tower main body, and an exhaust gas injected into the adsorption tower main body by the adsorbent. The present invention relates to a gas treatment device having a clean air discharge pipe that discharges clean gas from which air is removed into the atmosphere, and particularly to an exhaust gas treatment device that can slow down the rate of decline in the adsorption capacity of an adsorbent.

[0002] In factories that manufacture semiconductor devices, etc.,
Many types of chemicals, ie, emissions, that easily volatilize into the atmosphere are used. The atmosphere containing such exhaust substances, that is, exhaust gas, is discharged into the atmosphere after the exhaust gases are removed by an exhaust gas treatment device.

0003

2. Description of the Related Art Next, a conventional exhaust gas treatment device will be explained with reference to FIG. FIG. 3 is a diagram for explaining a conventional exhaust gas treatment device, in which FIG. 3(a) is a side sectional view schematically showing the main parts of the device, and FIG. Figure (c) is a side sectional view schematically showing the state of the adsorbent in which stirring is substantially stopped. In this specification, the same parts, materials, etc. are given the same reference numerals throughout the drawings.

A conventional exhaust gas treatment device is shown in FIG.
As shown in FIG. 1, there is an adsorption tower main body 11 in the shape of a large drum, in which exhaust gas 51 is introduced from an exhaust gas introduction pipe 12, and exhaust substances (not shown) contained in the exhaust gas 51 are removed. , a chimney-shaped clean gas discharge pipe 13 that is vertically installed on the ceiling of the adsorption tower main body 11 and communicates the inside of the adsorption tower main body 11 with the atmosphere, and a plurality of ventilation holes 16a.
are scattered, and one adsorbent falling port 16b is provided.
In the adsorption tower main body 11, four ventilation plates 16 are arranged so that the adsorbent drop ports 16b, which are spaced apart in the vertical direction and directly above or below each other, do not overlap with each other, and a ventilation cylinder 17a. and an umbrella-shaped adsorbent fall prevention 17b disposed directly above the ventilation cylinder 17a, and the adsorption tower main body 1
1, the ventilation cylinder 17a is directed upward and the inclined plate 17 is arranged directly below the ventilation plate 16 at the lowest stage.
An adsorbent regenerating device (not shown), which is part of the exhaust gas treatment device, is mounted obliquely on the upper side wall of the adsorption tower main body 11 and is mounted on the uppermost ventilation plate 16 disposed inside the adsorption tower main body 11. ) and an adsorbent supply pipe 18 that continuously supplies the adsorbent 52 that has been regenerated and sent by the adsorption tower main body 11, and an adsorbent falling port 16b of the lowermost ventilation plate 16, which is installed diagonally at the lower part of the side wall of the adsorption tower main body 11.
The system includes an adsorbent recovery pipe 19 for returning the spent adsorbent 53 that has continuously fallen from the pipe and slid down the inclined plate 17 to the adsorbent regenerating device.

The exhaust gas introduction pipe 12, which has one end connected to the adsorption tower main body 11, has one end connected to an exhaust gas generation source (not shown), and has one end connected to an exhaust gas generation source (not shown) to suck the exhaust gas 51 from the one end. It communicates with the other end of the duct 20. The exhaust gas introduction pipe 12 is equipped with a first blower 2 that sends the exhaust gas 52 from the exhaust duct 20 to the exhaust gas introduction pipe 12.
1, and an exhaust gas 51 disposed immediately before the adsorption tower main body 11.
a second blower 22 that vigorously sends the gas into the adsorption tower main body 11; an outside air intake pipe 23 and an exhaust gas emergency release pipe 25 that communicate with the exhaust gas introduction pipe 12 between the first blower 21 and the second blower 22; and are provided. In addition, the exhaust gas emergency release pipe 14 and the outside air intake pipe 23 are
A discharge pipe regulating valve 15 and an intake pipe regulating valve 24 are provided, which can freely adjust the opening to closing of each pipe.

[0006] Such an exhaust gas treatment device uses exhaust gas generated from an exhaust gas generation source in a semiconductor manufacturing factory, for example, to exhaust gas into an exhaust duct 20.
The exhaust gas 51 sent via the first blower 2
1 into the exhaust gas introduction pipe 12, and the exhaust gas 51 is energized by the second blower 22 and blown forcefully into the adsorption tower main body 11 to form an inclined plate 17 disposed inside the adsorption tower main body 11. The air is blown up vigorously from the ventilation tower 17a, and the air is sequentially moved upward and passed through the ventilation holes 16a of the ventilation plate 16 (see FIG. 12(a)).

[0007] Therefore, the exhaust gas 51 is
When passing through the ventilation hole 16a with great force, the ventilation plate 16
While the upper adsorbent 52 is stirred, the adsorbent 52 removes the exhaust substances contained therein and becomes a clean gas, for example, clean air 55, which is released into the atmosphere from the clean gas discharge pipe 13. .

[0008]

[Problems to be Solved by the Invention] As mentioned above, in order to stir the adsorbent 52 with the ventilation plate 16, it is necessary to introduce the exhaust gas 51 into the adsorption tower main body 11 at a predetermined flow rate, for example, about 500 m3 per minute. There is.

However, when the exhaust gas 51 alone cannot achieve the required flow rate, the intake pipe regulating valve 24 of the outside air intake pipe 23
The atmospheric air 54 was taken in from the outside air intake pipe 23, fed into the exhaust gas introduction pipe 12, and mixed with the exhaust gas 51, so that the total flow rate was about 500 m3.

However, during the rainy season or on a rainy day, the exhaust gas 51 mixed with high humidity outside air is removed from the adsorption tower main body 11.
When the adsorbent 52 is passed between the adsorbents 52 on the ventilation plates 16 disposed inside the exhaust gas 51, the adsorbent 52 adsorbs a large amount of moisture contained in the exhaust gas 51, and its adsorption capacity rapidly decreases.

[0011] Therefore, it is necessary to increase the amount of adsorbent 52 supplied from the adsorbent supply pipe 18 into the adsorption tower main body 11.
This also increases the amount of used adsorbent 53 to be recovered via the adsorbent recovery pipe 19, and increases the cost of regenerating the used adsorbent 53 into the original adsorbent 52 using the adsorbent regeneration device. The problem was that it was increasing.

The present invention has been made to solve these problems, and its purpose is to provide an exhaust gas treatment device that can maintain the adsorption ability of an adsorbent for a long time.

[0013]

[Means for Solving the Problems] The object is to provide an adsorbent 52 that adsorbs exhaust substances contained in exhaust gas, as shown in FIG.
an adsorption tower main body 11 containing an adsorption tower main body 11, an exhaust gas introduction pipe 12 that introduces exhaust gas into the adsorption tower main body 11, and a clean gas obtained by removing the exhaust gas from the exhaust gas by an adsorbent 52 in the adsorption tower main body 11. Clean gas discharge pipe 13 that discharges into the atmosphere
and an exhaust gas emergency release pipe 14 equipped with a discharge pipe adjustment valve 26 that freely adjusts a pipe connected to the exhaust gas introduction pipe 12 from an open state to a closed state. 12 and the clean gas discharge pipe 13, and a reflux means 32 for refluxing the clean gas passing through the clean gas reflux pipe 31 to the exhaust gas introduction pipe 12. This is achieved by the exhaust gas treatment device according to claim 1.

[0014] Also, the object is to provide an exhaust gas treatment apparatus according to claim 1 as shown in FIG. a bypass pipe 41 that communicates with the exhaust gas introduction pipe 12 at a position upstream from the connection position; a bypass pipe regulating valve 42 that is disposed in the bypass pipe 41 and alternately opens and closes the passage of the bypass pipe 41; , an introduction pipe adjustment valve 43 which is disposed in the exhaust gas introduction pipe 12 and freely adjusts the passage of the exhaust gas introduction pipe 12 between the clean gas recirculation pipe 31 and the bypass pipe 41 from an open state to a closed state; , an adsorption filter 44 that adsorbs exhaust substances contained in the exhaust gas when the exhaust gas passes through the exhaust gas emergency release pipe 14;
This can also be achieved by the exhaust gas treatment device according to claim 2, characterized in that the exhaust gas emergency release pipe 14 is provided with:

[0015]

[Operation] In both the exhaust gas treatment apparatus according to claims 1 and 2 of the present invention, clean gas, for example, clean air, released into the atmosphere from the clean gas discharge pipe 13 is introduced into the adsorption tower main body 11 from the exhaust gas introduction pipe 12. The flow rate of the exhaust gas sent into the adsorption tower body 11 is kept constant.

Therefore, since the moisture contained in the exhaust gas sent into the adsorption tower main body 11 decreases, the rate of decrease in the adsorption capacity of the adsorbent 52 decreases, and the recovery cycle of the used adsorbent 53 decreases. will be longer.

[0017]

[Example] Hereinafter, an exhaust gas treatment device of an embodiment according to claim 1 of the present invention (hereinafter referred to as a first embodiment) and an exhaust gas treatment device of an embodiment according to claim 2 (hereinafter referred to as a second embodiment) will be described. example)
will be described with reference to FIGS. 1 and 2, respectively. FIG. 1 is a side sectional view of a main part schematically showing a first embodiment, and FIG. 2 is a side sectional view of a main part schematically showing a second embodiment.

The first embodiment, as shown in FIG. 1, uses an outside air intake pipe 23 of the conventional exhaust gas treatment device explained with reference to FIG.
A clean gas recirculation pipe 31 configured such that one end on the atmosphere side is connected to the clean gas discharge pipe 13, and a clean gas discharge pipe 13 in place of the intake pipe regulating valve 24 disposed on the clean gas recirculation pipe 31.
A recirculation means, for example, a third blower 32, is provided to recirculate clean gas, such as clean air, released from the exhaust gas into the atmosphere from a clean gas recirculation pipe 31 to the exhaust gas introduction pipe 12.

Therefore, in the first embodiment, the clean gas, for example, clean air, released into the atmosphere from the clean gas discharge pipe 13 is refluxed to the exhaust gas fed into the adsorption tower main body 11 from the exhaust gas introduction pipe 12. Since the flow rate of the exhaust gas fed into the adsorption tower main body 11 is kept constant and the moisture contained in the exhaust gas sent into the adsorption tower main body 11 is reduced, the rate at which the adsorption capacity of the adsorbent 52 decreases is reduced. This lengthens the collection cycle of the used adsorbent 53.

Next, the second embodiment is constructed based on the first embodiment. That is, in the first embodiment, one end is communicated with the clean air discharge pipe 13, and
A bypass pipe 41 whose other end communicates with the exhaust gas introduction pipe 12 at a position upstream from the connection position of the clean gas recirculation pipe 31 and the exhaust gas introduction pipe 12, and a pipeline of the bypass pipe 41 can be freely changed from an open state to a closed state. Bypass pipe adjustment valve 4 that can be adjusted to
2, an inlet pipe adjustment valve 43 which is disposed in the exhaust gas inlet pipe 12 and can freely adjust the gap between the clean gas recirculation pipe 31 and the bypass pipe 41 from an open state to a closed state, and an exhaust gas emergency release pipe 14 An adsorption filter 44 that adsorbs exhaust substances when the exhaust gas 51 passes into the exhaust gas emergency release pipe 14 is disposed inside the exhaust gas emergency release pipe 14.

Therefore, in the second embodiment, during steady operation, the bypass pipe regulating valve 42 provided in the bypass pipe 41 closes the pipe, and the exhaust gas emergency release pipe 14 Since the pipe regulating valve 15 closes the pipe and the introducing pipe regulating valve 43 disposed in the exhaust gas introducing pipe 12 opens the pipe, the first
It will be operated under the same conditions as the embodiment.

Furthermore, for some reason, the vent hole 16a of the vent plate 16 becomes clogged with the adsorbent 52 or the spent adsorbent 53, as shown in FIG. 51 suddenly deteriorates, the bypass pipe regulating valve 42 disposed on the bypass pipe 41 opens the pipe, and the discharge pipe regulating valve 15 disposed on the exhaust gas emergency release pipe 14 opens the pipe. When the passage is opened and the passage is closed by the introduction pipe adjustment valve 43 disposed in the exhaust gas introduction pipe 12, the exhaust gas 51 sent into the exhaust gas introduction pipe 12 by the first blower 21 is transferred to the bypass pipe 4.
1 and then passed through the clean gas recirculation pipe 31, it is energized by the third blower 32 and the discharge pipe regulating valve 15
The exhaust gas passes through the exhaust gas emergency release pipe 14 whose pipe line has been opened, and at that time, exhaust substances are removed by the adsorption filter 44 and released from the exhaust gas emergency release pipe 14 into the atmosphere.

Therefore, in the second embodiment, even when the exhaust gas 51 is urgently released into the atmosphere from the exhaust gas emergency release pipe 14, the exhaust substances can be removed and released.

[0024]

As described above, the present invention can provide an exhaust gas treatment device that can slow down the rate of decline in the adsorption capacity of an adsorbent. Therefore, in the exhaust gas treatment device of the present invention, the regeneration cycle of the adsorbent is extended, so the cost of regenerating the adsorbent is reduced.

[Brief explanation of the drawing]

FIG. 1 is a side cross-sectional view of a main part schematically showing a first embodiment;

FIG. 2 is a side cross-sectional view of a main part schematically showing a second embodiment;

FIG. 3 is a diagram for explaining a conventional exhaust gas treatment device.

[Explanation of symbols]

11 is an adsorption tower main body, 12 is an exhaust gas introduction pipe, 13 is a clean gas release pipe, 14 is an exhaust gas emergency release pipe, 15 is a release pipe adjustment valve, 16 is a ventilation plate, 16a is a communication 16b is an adsorbent falling port, 17 is an inclined plate, 17a is a ventilation pipe, 17b is an adsorbent fall prevention, 18 is an adsorbent supply pipe, 19 is an adsorbent recovery pipe, 20 is an exhaust duct, 21 is a first blower, 22 is a second blower, 23 is an outside air intake pipe, 24 is an intake pipe adjustment valve, 31 is a clean gas recirculation pipe, 32 is a third blower (reflux means), 41 is a bypass pipe, 42 is a bypass pipe adjustment valve, 43 is an introduction pipe adjustment valve, 44 is an adsorption filter, 51 is an exhaust gas, 52 is an adsorbent, 53 is a used adsorbent , 54 represents the atmosphere, and 55 represents clean air (clean gas).

Claims (2)

[Claims] Claim 1: An adsorption tower main body (11) containing an adsorbent (52) that adsorbs exhaust substances contained in exhaust gas, and an exhaust gas introduction pipe (12) that introduces exhaust gas into the adsorption tower main body (11). ), a clean gas discharge pipe (13) for releasing clean gas into the atmosphere after the exhaust gas is removed with the adsorbent (52) in the adsorption tower main body (11), and an exhaust gas introduction pipe ( 12) in an exhaust gas treatment device comprising an exhaust gas emergency release pipe (14) and a discharge pipe adjustment valve (15) that freely adjusts a pipe communicating with the pipe from an open state to a closed state; (12) and the clean gas discharge pipe (13) communicate with each other (
31); and a reflux means (32) for refluxing the clean gas passing through the clean gas reflux pipe (31) to the exhaust gas introduction pipe (12). 2. The exhaust gas treatment device according to claim 1, which communicates with the clean gas discharge pipe (13), and connects the clean gas recirculation pipe (31) with the exhaust gas introduction pipe (13).
12) and a bypass pipe (41) that communicates with the exhaust gas introduction pipe (12) at a position upstream from the connection position with a bypass pipe regulating valve (42) that can be freely adjusted from a closed state to a closed state; and a bypass pipe regulating valve (42) that is disposed in the exhaust gas introduction pipe (12) and is provided between the clean gas recirculation pipe (31) and the bypass pipe (41). An inlet pipe regulating valve (
43), and an adsorption filter (44) that adsorbs exhaust substances contained in the exhaust gas when the exhaust gas passes through the exhaust gas emergency release pipe (14).
) An exhaust gas treatment device characterized by being disposed within.