JPH07194922A - Gas treatment method using activated carbon mat and apparatus for the same - Google Patents

Abstract

PURPOSE:To provide a gas treatment method using an activated carbon mat which improves the recovery efficiency of harmful gas, reduces gas quantity after concentration, increases gas concentration, and thereby downsizes a direct combustion apparatus, a catalytic oxidation apparatus, a recovery apparatus, etc., which are used in the next stage and to provide an apparatus for the method. CONSTITUTION:An apparatus is composed of endless belts l, 2 of a mat containing activated carbon, a driving means 3 for circulating the belts, an untreated gas supply means 5 which is arranged along the circuit of the belts 1, 2 and feeds treatment gas vertically from one side of the belt, and cells 4a, 4b which are arranged on the other side of the belt to face the means 5. The apparatus is also equipped with a discharge means 4 for taking out gas purified by filtration and desorption means 8, 9 which are arranged along the circuit and desorbs gas components adsorbed by the belts 1, 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention uses an activated carbon mat which filters harmful gases such as solvent vapors, chloroform and ether floating in the air, or odorous components, and concentrates and collects the recovered toxic gas / odorous components. The present invention relates to a gas treatment method and an apparatus therefor.

[0002]

2. Description of the Related Art Conventionally, a solvent adsorption / desorption device has been developed for treating a low-concentration exhaust gas which is apt to be left unattended, for continuously recovering the solvent in the exhaust gas by repeating adsorption and desorption. This type of apparatus is configured to rotate a tubular body formed by honeycomb-shaped paper made of activated carbon fiber, and to supply exhaust gas and heating gas for desorption. In this structure,
Since the exhaust gas flows in parallel to the adsorption surface, the ventilation pressure loss becomes extremely small as compared with, for example, when the exhaust gas is passed through the felt layer, and therefore the adsorption wind speed can be greatly improved.

[0003]

However, in the above-mentioned honeycomb type solvent recovery apparatus, there is an advantage that the ventilation pressure loss is small, but on the other hand, a sufficient contact area can be given to the exhaust gas as the gas to be treated. However, there is a problem that the untreated gas passing through without being adsorbed is exhausted as it is. Further, the adsorbed exhaust gas has a low concentration and is treated in the next step, for example, a catalytic oxidation device,
There is a problem that the configuration of the recovery device and the like becomes large.

The present invention has been made in consideration of the above problems of the conventional solvent recovery apparatus, and improves the recovery efficiency of the gas to be treated, reduces the amount of gas after concentration, and increases the concentration thereof. The object is to provide a gas treatment method using an activated carbon mat and a device therefor capable of reducing the size and simplification of the configurations of a direct combustion device, a catalytic oxidation device, a recovery device, etc., which are used in the next step. And

[0005]

According to the present invention of claim 1, a band-shaped endless mat containing activated carbon is circulated, and a gas to be processed is supplied in a thickness direction of the band-shaped endless mat so that a gas component to be processed is banded. In this gas treatment method, a gas component adsorbed on a mat and adsorbed on the band-shaped endless mat is desorbed on the downstream side of the adsorption section in the band-shaped endless mat orbit.

According to a second aspect of the present invention, the belt-shaped endless mat containing activated carbon, the driving means for orbiting the belt-shaped endless mat, and the belt-shaped endless mat are arranged along the orbit of the belt-shaped endless mat in the thickness direction of the belt-shaped endless mat. A means for supplying a gas to be processed from one side, and a compartment arranged on the other side of the band-shaped endless mat facing the gas to be processed means for taking out the purified gas. And a desorption means for desorbing the gas component adsorbed on the band-shaped endless mat, which is arranged along the circular orbit, and is a gas treatment device using an activated carbon mat.

In the present invention, the band-shaped endless mat has a band-shaped activated carbon mat and an air-permeable endless belt which is provided inside the band-shaped activated carbon mat and causes the band-shaped activated carbon mat to circulate together with the band-shaped activated carbon mat. It is preferable that it is formed to be slightly shorter so as not to give tension to the strip-shaped activated carbon mat.

In the present invention, the compartment is composed of a double-structured partition having an air gap and has an opening on the side of the band-shaped endless mat, and the outer edge and the inner edge of the partition respectively contact the inner surface of the band-shaped endless mat to purify it. It is preferable that the gas is taken out from the inner partition wall, and the unprocessed gas which is going to enter the inner partition wall as the belt-shaped endless mat goes around is taken into the void and sent to the target gas supply means.

[0009]

According to the present invention, the band-shaped endless mat containing activated carbon is circulated, and the gas to be processed is supplied in the thickness direction of the band-shaped endless mat so that the gas component to be processed is adsorbed to the band-shaped mat and the purified gas is obtained. The gas component that has been filtered and adsorbed on the belt-shaped endless mat is desorbed on the downstream side of the adsorption section in the belt-shaped endless mat orbit, and is extracted as a concentrated gas.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the embodiments shown in the drawings. FIG. 1 shows the configuration of an embodiment of an apparatus used in the gas recovery / desorption method of the present invention.
(A) of the same figure is a front view of the apparatus, and (b) is a left side view of the apparatus.

The basic structure of the gas recovery / desorption apparatus is that the belt-shaped endless mat containing activated carbon, the driving means for orbiting the belt-shaped endless mat, and the belt-shaped endless mat are arranged along the orbit of the belt-shaped endless mat. A means for supplying a gas to be processed from one side to the chamber and a compartment arranged on the other side of the band-shaped endless mat facing the gas to be treated means for taking out the purified gas. When,
Desorption means arranged on the downstream side of the extraction means in the circular orbit, for desorbing the gas component adsorbed on the belt-shaped endless mat,
It is equipped with.

The structure of each unit will be described below. FIG. 2 shows the structure of a strip-shaped activated carbon mat (hereinafter referred to as activated carbon mat) 1, where (a) is a front view and (b) is an AA cross-sectional view. The activated carbon mat 1 is formed by using a needle punch method together with a non-woven fabric 18 made by mixing activated carbon fiber felt (basis weight of 200 to 1000 g / m ² ) with rayon, ester, or both. The widthwise end faces 1a and 1b of the activated carbon mat 1 are reinforced with a reinforcing material 19 such as cloth, and further reinforced to prevent elongation due to its own weight. Specifically, this reinforcement is made up of a few pieces in the longitudinal direction of the activated carbon mat 1 (50 to 100 mm intervals in the width direction).
It is made by sewing the applied mesh 20 or a suitable tape.

A breathable endless belt (hereinafter referred to as a belt-like belt) 2 for circulating the activated carbon mat 1 is provided inside the activated carbon mat 1 and is a fiber such as aramid fiber, Teflon, or steel which is hard to expand and contract. It is composed of a net-like belt of several mesh woven using. The belt-shaped belt 2 has a circumferential length slightly shorter than that of the activated carbon mat 1 so that no tension is applied to the activated carbon mat 1. The activated carbon mat 1 and the belt-shaped belt 2 described above can be regarded as a belt-shaped endless mat.

The driving means includes four belt driving rolls 3a to 3d which are arranged to face each other on the upper side and the lower side with the adsorption chamber 4 sandwiched therebetween, and a belt pressing unit which is arranged above the belt driving rolls 3a to 3b. It is mainly composed of rolls 3e to 3h. The belt-shaped belt 2 on which the activated carbon mat 1 is placed is stretched around the belt driving rolls 3a to 3d and is sandwiched by the belt pressing rolls 3e and 3h so that it can be rotated. As described above, the activated carbon mat 1 is not fixed to the belt belt 2 and has a slightly longer circumferential length than the belt belt 2. Therefore, the activated carbon mat 1 has the belt drive rolls 3c and 3c.
It is in a loose state below d, so that tension is not applied to the activated carbon mat 1.

The raw gas duct 5 as a means for supplying a gas to be treated is arranged along the circular orbits of the band-shaped endless mats 1 and 2, and the gas to be treated is supplied from one side in the thickness direction thereof. The gas to be treated is a harmful gas such as solvent vapor, chloroform and ether.

An adsorption chamber (adsorption portion) 4 as an extraction means is for purifying harmful gas from the other side of the band-shaped endless mats 1 and 2, and its compartment is a double-structured partition having a void 7. The strip-shaped endless mats 1 and 2 have openings, and the outer and inner edges of the partition walls come into contact with the inner surface of the strip-shaped endless mat, respectively, and the purified gas is taken out from the inner partition wall 4a. The untreated gas which is about to enter the inner partition wall 4a during the circulation of the above is taken into the void 7, and then sucked from the slit 4c having a width of 1 to 5 mm provided in the outer partition wall 4b, and the return duct 14
It is designed to be returned to the original gas duct 5 via.

The desorption means includes a desorption gas supply fan 12, a heater 13, a desorption heating air supply chamber 8, a desorption heating air supply duct 10 connecting these in this order, a post-desorption exhaust gas duct 9 and a desorption gas duct connected thereto. 11 and 11. The harmful gas component adsorbed on the activated carbon mat 1 is sent by the desorption gas supply fan 12 when passing through the desorption chamber 8 and is heated by the heater 13 at 1000 ° C. or higher, generally 100 to 15
It is desorbed by the gas heated to 0 ° C., and then exhausted from the desorption gas duct 11. The desorption gas amount at this time is a gas amount of several tenths or more of the original gas amount, and is generally 1/2 to 1/30. Therefore, the gas concentration discharged from the desorption gas duct 11 is The gas amount / desorption gas amount is doubled. Therefore, the amount of gas after concentration is small and the concentration is high, so that the processing apparatus used in the next step can be small and have a simple structure. In the figure, reference numeral 15 is a meandering prevention bar for preventing meandering of the activated carbon mat 1, 16 is a raw gas suction fan, and 17 is a case for accommodating the above-mentioned components.

The operation of this embodiment having such a configuration will be described below. The belt-shaped belt 2 circulates in the direction of arrow B while being in contact with the outer edge and the inner edge of the adsorption chamber 4,
Accordingly, when the gas to be treated is applied to the activated carbon mat 1 while the activated carbon mat 1 orbits in the same direction,
The harmful gas component is filtered by the activated carbon mat 1 to become a purified gas, which is introduced into the inner partition wall 4 a of the adsorption chamber 4 and discharged from the exhaust gas duct 6 to the outside. At this time, some unprocessed gas enters along the belt-shaped endless belts 1 and 2 that circulate, and the unprocessed gas that has entered is sucked into the gap 7 of the adsorption chamber 4 and sucked from the slit 4c. It is returned to the raw gas duct 5.

The belt-shaped endless mats 1 and 2 having adsorbed harmful components in the gas to be treated are belt drive rolls 3d → 3c → 3b.
After that, it is sent to the position of the desorption heating air supply chamber 8 and desorbed by the heating gas, and after desorption, it is collected in the exhaust gas duct 9. In this way, the strip-shaped endless mats 1 and 2 are
Adsorption and desorption of harmful components are repeated in the process of orbiting. In addition, since the activated carbon mat 1 is loosely configured, no tension is applied, and therefore the activated carbon mat 1 can orbit without being damaged.

The breathable endless belt of the present invention is not limited to the net belt using the fibers as in the above embodiment,
Any material can be used as long as it can support the activated carbon mat and has a ventilation function, such as a punching metal sheet or a ring-shaped wire made of a plurality of sheets.

Further, the strip-shaped activated carbon mat of the present invention is made of the activated carbon fiber felt formed into a mat shape by the needle punch method together with the non-woven fabric made of synthetic fibers in the above embodiment, but the present invention is not limited to this. Alternatively, the activated carbon particles may be enclosed with a non-woven fabric and provided with a reinforcing material to prevent the elongation in the longitudinal direction, or the activated carbon particles may be formed of a web impregnated with a fiber material such as rayon or pulp.

Further, the strip-shaped activated carbon mat of the present invention may be one in which activated carbon fibers produced from rayon, vinylon, acrylic fiber or the like as a raw material are directly formed into a non-woven fabric and further formed into a mat shape. Further, the gas treatment apparatus of the present invention has a vertical position in the above-mentioned embodiment, but it may be a horizontal position with the opening edge of the adsorption chamber facing upward. The gas treatment device of the present invention can be applied not only to the above-mentioned harmful gas but also to desorption of malodorous components.

[0023]

As is apparent from the above description, according to the present invention, the purification efficiency of exhaust gas can be increased, the amount of gas after concentration can be reduced, and the concentration can be increased. It has an advantage that the structures of the direct combustion device, the catalytic oxidation device, the recovery device and the like used can be downsized and simplified.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing the configuration of an embodiment of a gas recovery / desorption device of the present invention.

FIG. 2 is an explanatory view showing the structure of an activated carbon mat used in the same example.

[Explanation of symbols]

 1 activated carbon mat 2 belt belt 3 belt drive roll 4 adsorption chamber 4a inner partition wall 4b outer partition wall 5 raw gas duct 6 post-treatment exhaust gas duct 7 void 8 desorption heating air supply chamber 9 desorption exhaust gas duct 10 desorption heating air supply duct 11 desorption Gas duct 12 Desorption air supply fan 13 Heater 14 Return gas duct 15 Meandering prevention bar 16 Raw gas suction fan

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Seiichi Takahashi 6-10 Ioyama-cho, Nada-ku, Kobe City Konan Oken Co., Ltd.

Claims (4)

[Claims] 1. A belt-shaped endless mat containing activated carbon is circulated, and a gas to be treated is supplied in a thickness direction of the belt-shaped endless mat to adsorb the gas component to be treated to the belt-shaped mat, and the belt-shaped endless mat. The gas treatment method characterized in that the gas component adsorbed on the strip-shaped endless mat orbit is desorbed on the downstream side of the adsorbing portion. 2. A belt-shaped endless mat containing activated carbon, a driving means for orbiting the belt-shaped endless mat, and arranged along a circular orbit of the belt-shaped endless mat, from one side in a thickness direction of the belt-shaped endless mat. A to-be-processed gas supply means for supplying a to-be-processed gas, and a take-out means for taking out the filtered purified gas having a compartment arranged on the other side of the band-shaped endless mat facing the to-be-processed gas supply means. And a desorption unit arranged along the circuit orbit for desorbing the gas component adsorbed on the band-shaped endless mat, the gas treatment apparatus using an activated carbon mat. 3. The belt-shaped endless mat has a belt-shaped activated carbon mat and an air-permeable endless belt which is provided inside the belt-shaped activated carbon mat to circulate around the belt-shaped activated carbon mat together, and the endless belt has a circumference of the belt-shaped activated carbon mat. The gas treatment device according to claim 2, wherein the gas treatment device is formed so as to be slightly shorter than the circumferential length and does not apply tension to the strip-shaped activated carbon mat. 4. The compartment comprises a double-structured partition having an air gap, and has an opening on the side of the band-shaped endless mat, and an outer edge and an inner edge of the partition contact the inner surface of the band-shaped endless mat, respectively. The cleaning gas is taken out from the inner partition wall, and the untreated gas which is about to enter the inner partition wall along with the circulation of the band-shaped endless mat is taken into the void and sent to the target gas supply means. The gas treatment apparatus according to claim 2 or 3, wherein.