JP2011025219A - Exhaust gas cleaning method containing water-soluble volatile hydrocarbon of large amount and high humidity - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a treating method of a large amount of exhaust gas exceeding 10,000 m<SP>3</SP>/h of high humidity of 50% or more of R.H., and containing lean water-soluble VOC of several hundred to several thousand ppm in the exhaust gas. <P>SOLUTION: In an exhaust gas treating method, an adsorbing apparatus is used for treating the exhaust gas containing lean water-soluble hydrocarbon and a large amount of moisture. The adsorbing apparatus consists of a layer packed with zeolite-made honeycomb or zeolum-made honeycomb as an adsorbent, so-called a molecular sieve adsorbent, wherein a pre-stage alternately performing adsorption and desorption, is packed with a honeycomb layer formed of zeolite or zeolum having a pore diameter of about 3 Å and/or a honeycomb layer consisting of hydrophobic silica gel, and a rear stage is packed with particulate meso-hole activated carbon and/or hydrophobic silica gel, with the upper and lower stages communicated with each other. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to a method for purifying a large amount of humid exhaust gas containing humid air filled in a room, high-humidity atmospheric gas containing odor, and / or water-soluble and dilute volatile hydrocarbons. While processing a large amount of high-humidity exhaust gas containing extremely dilute water-soluble VOCs with odors diffused in it, the living space is kept comfortable while concentrating the water-soluble VOCs contained This is a device that is used for recovery as it is, and like the “desiccant rotor” that has been used in the past, it requires a temperature of 200 to 300 ° C. for desorption operation, and it is warmed by burning it freely. instead of being released into the atmosphere as a carbon dioxide gas has been questioned (CO ₂₎ gas, dropped from the point of view of the perspective and pollution prevention of global warming, to almost zero PPM moisture in said exhaust gas odor In addition to the purpose of separating and recovering components and purifying living spaces, a dilute VOC related to an adsorption method for efficiently separating and reusing water-soluble VOC, which is one of the odor components, from the exhaust gas. The present invention relates to a large amount and high humidity exhaust gas purification method.

  Conventionally, many methods for treating exhaust gas containing VOC have been proposed. In other words, from the viewpoint of pollution prevention, combustion methods, adsorption methods, absorption methods, membrane methods, etc. are known as means for removing VOCs in exhaust gas to satisfy legally required VOC emission concentration regulation values. It has been.

However, the above method is limited to the case where the amount of exhaust gas to be treated is several hundred to several thousand m ³ per hour and the concentration of VOC contained is relatively high on the order of%. Among them, as a method for treating a large amount of exhaust gas containing a thin and water-soluble VOC on the order of PPM, a high-silica zeolite is used as an adsorbent, and this dilute honeycomb rotor rotates alternately and repeatedly by adsorption and desorption. The only combustion method that has been widely used, apart from whether it is concentrated to a few thousand PPM for catalytic combustion or by direct combustion method, is the recent strengthening of greenhouse gas (carbon dioxide) emission regulations This led to a situation where it was extremely difficult to apply.

  Based on this situation, the adsorption method, absorption method, membrane separation method, or fibrous activated carbon method has attracted attention as an applied technology that can recover VOC without burning. In the case where there is no affinity for moisture as described above, a technology has been developed that enables efficient recovery in the dry state without using steam when adsorbing and desorbing. For example, with respect to the adsorption method, there is no problem in enumerating the following Patent Document 1, Patent Document 2, Patent Document 3, Patent Document 4, Patent Document 4, Patent Document 5, and the like.

Japanese Patent Laid-Open No. 9-47635 Japanese Patent Laid-Open No. 9-57060 JP-A-9-215908 Japanese Patent Laid-Open No. 11-71584 Japanese Patent Laid-Open No. 11-77495 JP 2002-293754 A Japanese Patent Laid-Open No. 2003-154027 JP 2007-38201 A

However, when the contained VOC is water-soluble, such as methanol or ethanol, it is difficult to efficiently separate it from moisture contained in high-humidity air. For example, it is disclosed in Patent Document 7 above. In addition, there is an application example to a so-called gas mask in which activated carbon carrying various metals is used to decompose water-soluble VOC, such as methanol, by catalytic action and simultaneously decomposed. The activated carbon that was used cannot be reused and is discarded. Moreover, as described above, the application examples are limited to exhaust gas treatment of several hundred to ^three thousand m ³ at most including RH and a rich VOC.

In order to solve the problem, the present inventor, as proposed in the above-mentioned Patent Document 6, finely divides the moisture in the VOC mixed gas containing a large amount of moisture under the trade name of 3A Zeorum (Tosoh Corporation). ) And pre-adsorbed to remove water-soluble VOCs contained in exhaust gas, that is, ethyl acetate, ethanol, butanol, We succeeded in recovering ethanol with a purity close to 100%. However, in the multi-layer packing method using fine zeolam 3A, if the rising speed of the exhaust gas passing through the adsorbent layer is too high (limited to about 30 cm per second), the adsorbent with a small particle size rises and causes a flooding phenomenon. For this reason, if the processing is performed at the limit of the second speed, if the amount of exhaust gas to be processed is 1000 m ³ or more per hour, the size of the device becomes enormous and it is not economically established. In addition, as can be seen in the case of the adsorption method using fibrous activated carbon, even if adsorption can be performed at a speed exceeding 1 m / s, steam is always required for desorption, so the moisture accompanying the desorbed VOC ( (Liquid) cannot be discarded as it is, and the water treatment facility is expensive.

  As cited above, in the method disclosed in the above-mentioned Patent Document 8 and the method (Japanese Patent Application No. 2008-2635) filed later by the present applicant as a further improvement method, the first stage is a mesopore. A honeycomb adsorbent made of activated carbon and / or a corrugated layer made of hydrophobic silica gel is filled, and a granular mesopore (pore) activated carbon and / or a granular hydrophobic silica gel layer is filled in the subsequent stage, and they are communicated with each other vertically. By using the adsorption tower, the still diluted VOC adsorbed in the former stage is drawn into the latter stage and stored, and as a means for further concentration, a vacuum pump provided at the lower part of the latter stage is used as the means for the former stage. An operation method in which the VOC remaining after the moisture is removed is passed through the latter stage, that is, the lower stage processing apparatus, and further concentrated in the latter stage is a high humidity. Experiments have confirmed that the VOC present in the exhaust gas is not necessarily the best equipment configuration only when processing gases when water-soluble volatile hydrocarbons such as methanol, ethanol, or ethyl acetate are treated. It was.

  The main cause is that the above-described method is such that the upper honeycomb adsorbent allows the moisture in the raw material gas to pass through, and adsorbs only volatile hydrocarbons insoluble in water, that is, mesoporous activated carbon or hydrophobic silica gel. This is because it is used.

  Therefore, the present inventors specified 3A zeolite which is famous as an adsorbent that does not cause the above-mentioned flooding phenomenon and adsorbs only moisture, so that it does not remain granular but is made into a honeycomb shape. The honeycomb-shaped adsorbent formed by adding the above binder is applied to the pre-concentration to adsorb only water, and the water-soluble VOC that has not been adsorbed in the pre-stage is taken out from the top of the tower and repeatedly supplied to the bottom of the post-stage. The VOC concentrated here is proposed by a method of recovering by a known technique by the present inventors.

That is, it is a method of pre-stage recovery and post-stage concentration, which is a dilute water-soluble VOC of several hundred to several thousand ppm in a large amount of exhaust gas having a high humidity of RH exceeding 50% and exceeding 10,000 m ³ per hour. It is providing the processing method in the case of including. Furthermore, the object of the present invention is proposed as a method that can be suitably applied as a dehumidifying purpose for living spaces.

  In order to achieve the above object, the exhaust gas purification method of the present invention includes a diluted VOC that dissolves in water and exhibits an azeotropic phenomenon with water, such as methanol and ethanol, and is capable of purifying a large amount of high-humidity exhaust gas. In contrast to the method previously proposed by the present inventors, the adsorbent is a honeycomb layer formed from zeolite or zeolite having a pore diameter of 3 mm at the previous stage of the adsorbing device. And / or a honeycomb layer composed of hydrophobic silica gel, and a large amount and a high amount of the adsorbing device in which upper and lower layers filled with granular or honeycomb mesoporous activated carbon and / or hydrophobic silica gel are connected in the subsequent stage. This is a method for treating exhaust gas containing moisture of humidity.

  Further, in the method for purifying a large amount of exhaust gas containing a dilute VOC according to the present invention, the desorption means of the adsorption / desorption device uses a small amount of warm air or nitrogen from the top of the adsorption device to a room temperature, and Adsorption device that uses a vacuum pump to change the adsorption / desorption switching time from 1 to 30 minutes, releases the obtained water out of the system, and does not contain water released from the previous stage during adsorption (Rear stage), repeatedly concentrated, concentrated to some extent (before breakthrough), then suctioned from the bottom of the apparatus using a vacuum pump and / or a small amount of air or nitrogen from the top, This is a method for recovering water-soluble VOCs present in humid air, in which the switching time between adsorption and desorption is 1 to 30 minutes, and the obtained moisture also serves as a dehumidifying device that releases it as it is.

  At this time, the cooled and uncondensed VOC gas is returned to the bottom of the latter adsorption device, the upper part is a purification section using a honeycomb, the lower part is granular or honeycomb-shaped mesopore activated carbon and / or granular. By using an integrated device with a hydrophobic silica gel concentration part, the processing gas speed passing through the preceding honeycomb layer is increased to 1 to 2 m per second, and a water-soluble diluted VOC passing through the preceding stage is obtained here. While concentrating to about 5-10 cultures, at the time of desorption, the concentrated gas is sucked and cooled by a vacuum pump, and the uncondensed gas at that time is returned to the bottom of the subsequent concentrated layer, thereby further enriching the VOC. To.

  In this way, by repeating this adsorption / desorption, a so-called cascade adapter (using uncondensed VOC for each desorption as a raw material) stores VOC corresponding to the equilibrium adsorption amount in the lower particle size adsorbent communicating with the upper stage. It is possible to play the role of an adsorption tower that collects, concentrates and accumulates in this tower without returning. With such an apparatus configuration and operation method, a water-soluble VOC such as methanol or ethanol contained in humid air can be easily liquefied even at room temperature and recovered as a liquid. Therefore, the VOC concentration in the gas discharged to the atmosphere can be reduced to almost zero ppm. Moreover, it is an epoch-making method that can be expected to have a dehumidifying effect. The cascade adapter method is described in detail in Japanese Patent No. 2766793 (Japanese Patent Laid-Open No. 9-57060) by the present inventors.

  Further, according to the present invention, a method for purifying a large amount and a high amount of exhaust gas containing dilute water-soluble VOC is obtained by using zeolite or zeolum (both granular or powdery at the time of shipment) as a honeycomb raw material used in the previous stage. It is characterized in that the binder indispensable for forming into a shape is a material obtained by mixing sepiolite and inorganic fibers and / or colloidal silica with an organic binder and then firing. This is because the moisture adsorbed on the molecular sieve usually requires a heating medium of 200 to 300 ° C. for desorption as described above, but the desorption conditions can be significantly changed by this operation.

  That is, it becomes possible to use hot air or nitrogen gas near room temperature as the purge gas. Thus, as described in claim 4, it becomes possible to recover the water-soluble VOC concentration contained in the humid exhaust gas treated by the above method at almost 100%. In addition, the zeolite or zeoram used in the present invention is Tosoh's Zeolum 3A (trade name) or Union Showa Co., Ltd. 3A to 4A (trade name). Any product name is acceptable.

  In the case of the present invention, the zeolite honeycomb layer having a three-pore diameter used in the upper stage should theoretically adsorb only water having a pore diameter of 2.8 liters, and there are many examples of application as a dehumidifying means. The desorbing means for the moisture required requires hot air of 300 to 400 ° C. In order to avoid this, the binder when forming into a honeycomb using the molecular sieve zeolite to be used becomes the object of know-how. Even in such a case, as a means for avoiding the use of hot air of about 300 ° C. for desorption, a vacuum pump is always required as a desorption means used in combination with a purge gas close to room temperature. However, at the time of adsorption, the concentration of the water-soluble VOC that is discharged into the atmosphere without being adsorbed by anything other than moisture is too dilute as it is and may not be able to be recovered, and at the same time, it is scattered as an air pollutant . At the same time, there is a method of introducing this dilute water-soluble hydrocarbon to a separately provided tower and washing it with an absorbing solution, but this is not economical.

  The biggest advantage of adopting honeycomb as the reason is that the adsorbent (adsorbent () In the case of the honey-comb honeycomb, the breakthrough of the bulk specific gravity is about 0.1) is quick. Incidentally, the bulk specific gravity of conventionally used granular activated carbon is around 0.5, and has an adsorption capacity of 4-5 cultures compared to a honeycomb. However, the rising speed of the gas causing the flooding (floating phenomenon) of the granular activated carbon layer is 0.3 m / s. Therefore, although the concentration ratio of the honeycomb, that is, the adsorption amount depends on the composition and filling amount of the honeycomb to be used, it is about 1/5 of the case where the main material is mesoporous activated carbon, but the adsorbent layer. It will be offset by the rising speed that passes through. Therefore, the selection of whether the adsorbent is granular or honeycomb depends on the amount of gas to be processed.

  Therefore, even if the concentration is on the order of PPM, the post-recovery device according to Patent Document 7 can recover almost 100% of the VOC, but the VOC contained in the exhaust gas is further diluted to several hundred ppm, Moreover, considering the case of treating a gas of several thousand to several tens of thousands of cubic meters per hour that is water-soluble and contains a large amount of water, after water is adsorbed in the former stage, water-soluble volatile hydrocarbons are subsequently used in the latter stage. The pros and cons of collecting the equipment is questioned. One reason is that it is not easy to desorb the adsorbed moisture.

  As conventionally known, two towers made of honeycomb layers are provided, and the adsorption and desorption operations are alternately performed, and exhaust gas obtained by suction with a vacuum pump used for desorption (in this case, moisture and a small amount of water-soluble) The method of repeatedly returning the non-condensed gas to one of the honeycombs after cooling the VOC) results in a very large capacity of the apparatus because the honeycomb adsorption capacity is small. In short, since the breakthrough is quick, the recovery rate of VOC in the air diffused into the atmosphere after operation is less than 80%, as described above. Separately from the vacuum pump for the former stage collection, the vacuum pump is necessary as the desorption means for the latter stage collection as well as the former stage. In addition, since the sequence operation is independent of each other, the economy is extremely high. Damaged.

It is the schematic which shows an example of the apparatus which concerns on a present Example.

  In the embodiment of the present invention, an adsorbent layer and a concentration are used in the treatment of a water-containing exhaust gas containing a large amount of dilute and water-soluble VOC, for example, methanol, ethanol, ethyl acetate and the like, and RH of 50% or more. It is an apparatus that integrates the agent layer into upper and lower parts, and the contained moisture is adsorbed on the honeycomb layer for the purpose of the molecular sieve effect provided in the upper stage, and the dilute gas discharged from the top of the tower at that time A water-soluble VOC is introduced into the mesoporous activated carbon (granular) provided in the lower stage, and a “concentrating agent layer” that is concentrated to about 5 to 10 cultures is connected here. This "honeycomb layer" is pre-coated with a humid exhaust gas containing the VOC in advance, for the following reason.

  That is, taking Zeolum 3A as an example, when humid air containing a small amount of methanol and having an RH of about 80 is allowed to flow through this layer, methanol is first adsorbed, and this methanol is replaced with moisture as moisture adsorption proceeds. Thus, the concentrated methanol is discharged to the atmosphere at the outlet of the adsorption tower. After that, as moisture is saturated and adsorbed, methanol is no longer adsorbed, and the above pre-coating operation is necessary due to the phenomenon that the methanol concentration (inlet) in the source gas becomes equal to the methanol concentration (outlet) in the atmospheric emission gas. That is why. For reference, the molecular diameter of water is about 2.7 mm, the molecular diameter of methanol is about 3.8 mm, and the molecular diameter of the honeycomb used is about 3 mm. This phenomenon is presumed to be due to the effect of sepiolite mixed in the 3Å zeolite honeycomb.

  The moisture adsorbed on the upper “honeycomb layer” should be desorbed as soon as possible (within 1 to 30 minutes, preferably about 10 minutes). The desorption means is a small amount of purge gas and / or vacuum pump. . The increase / decrease in the desorption time can be shortened depending on the amount of purge gas used in combination with the suction capacity (vacuum degree) of the vacuum pump, that is, the purge coefficient (α).

  Next, the water-soluble dilute VOC that has passed through the honeycomb layer is continuously led to a concentrated layer provided in a subsequent stage, that is, an adsorption tower filled with granular mesoporous activated carbon. The VOC concentrated to about 5 to 10 in this layer is taken out of the system by a vacuum pump by a method conventionally used by the present inventors. This concentrated layer has an adsorption pore size of 1 to 10 Nano-adsorbent layer filled with precoated particle size mesopore (pore) activated carbon and / or pre-coated hydrophobic silica gel with average adsorption pore size of 4 to 6 nano particle size Since the adsorption capacity is several times that of the honeycomb, the VOC accumulated at the bottom of the latter adsorbent layer, that is, the VOC that was not adsorbed by the previous honeycomb operation was returned to this layer and already accumulated. Combined with water-soluble hydrocarbons, it is present at the bottom as a more concentrated VOC.

  This VOC is taken out by a vacuum pump with a switching swing of about 5 minutes. By this repeated operation, the concentration of the water-soluble VOC passing through the upper stage becomes extremely high, and a large amount of VOC is converted into a liquid without lowering the cooling temperature so much. There is merit that can be recovered. Thus, since the treatment is performed using the adsorption tower in which the former stage and the latter stage are vertically communicated, it is also expected to be able to dehumidify the moisture in the atmospheric air containing the dilute and water-soluble VOC contained in a large amount of humid air. become able to do. In other words, it has a great effect on food storage warehouses that require long-term storage and comfort in living spaces, and depending on the cost, it can compete with conventional Freon air conditioning and desiccant air conditioning. I have a secret.

  The operation method in this apparatus is that the switching time of the adsorption / desorption operation is 1 to 30 minutes, preferably about 5 to 10 minutes, the purge operation is a vacuum pump and / or room temperature air or nitrogen, and / or Use with a vacuum pump. At this time, the remaining exhaust gas that has adsorbed moisture, that is, dilute water-soluble VOC is returned to the solid adsorbent provided in the subsequent stage, concentrated for easy removal, taken out of the system, and contained VOC as liquid While recovering, the uncondensed gas that could not be cooled is returned to the bottom of the concentrator. The type of the vacuum pump used in this method is not limited, but a liquid ring rotary pump is desirable, and the ultimate vacuum is sufficient if it is 3.5 Kpa. The purge gas used in combination may be nitrogen gas with little moisture.

[Exhaust gas targeted by the present invention]
The target gas in the present invention is a large amount of exhaust gas of several thousand to tens of thousands of m ³ or more discharged from a coating factory, a semiconductor factory, a manufacturing process for handling chemical products, etc. In addition, dilute water-soluble VOCs (for example, water-soluble alcohols such as methanol, ethanol, and ethyl acetate, and azeotropic phenomena, aromatic hydrocarbons such as benzene and toluene, butadiene, hexene, and styrene) And diene polymerized substances such as trichlene, methylene chloride and ethyl acetate). In addition, it is intended for exhaust gas with a concentration of several hundreds or thousands of PPM and containing a large amount of moisture and several thousand m ³ per hour. Living spaces that hate people are also targeted.

  An example of an apparatus that can be used in the method for purifying a large amount of water-containing gas (air) containing dilute water-soluble VOC according to the present embodiment will be described with reference to FIG. In this example, as shown in FIG. 1, a raw material exhaust gas supply line 1 by a blower, adsorption towers 1A and 1B filled with different adsorbents, a vacuum pump 4, a cooler 5 for separating gas and liquid, uncondensed gas By using this apparatus comprising the VOC gas line 9 discharged from the top of the return line 7, the recovered liquid take-out line 6, 1A (1B) and introduced into the lower adsorbent layer, and the purge gas supply line 9A, a diluted VOC is used. This is an example of processing a large amount of exhaust gas (humid air with high humidity). Note that 10A, 10B, 11A, 11B, 12A, 12B, 13A, 13B, 14A, 14B, 15A, and 15B are all electromagnetic valves. In the following, the constituent part including the preceding adsorption tower shown in the figure is referred to as A system, and the constituent part including the lower adsorption tower is referred to as B system.

  In this example, the adsorbent filled in the system A is a zeolite honeycomb having a pore size of 3 mm and / or a honeycomb made of hydrophobic silica gel, and the adsorbent filled in the system B is granular or honeycomb-shaped. Mesoporous activated carbon and / or hydrophobic silica gel is filled in a pre-coated state, or the pre-coating operation is completed before the apparatus is operated. Specifically, the A-type honeycomb layer is Zeolum 3A manufactured by Toso Co., Ltd., and the B-type concentrated layer is manufactured by Hinomaru Sangyo Co., Ltd. HPZ-11W (mesoporous activated carbon) and / or Fuji Silysia Chemical Ltd. It is a granular hydrophobic silica gel (trade names S-4, S-6).

  In this example, “air having a relative humidity (RH) of 80% containing 5000 PPM of ethyl acetate” was fed from the bottom of the system A at a rate of 100 cc / min. Before that, the adsorbent layer is precoated with the gas in advance. Further, the air feeding speed of the air passing through the raw material gas line 1 was about 1 second for the contact time with the agent and about 20 minutes for the switching time.

  As a verified result, it was confirmed that ethyl acetate was not adsorbed on the zeolite 3A honeycomb layer but only water was adsorbed. Next, the experiment when methanol vapor is mixed instead of ethyl acetate under the same conditions is as follows. The molecular diameter of methanol is 3.8 mm, but in this result, it flows into the A system. The phenomenon that methanol was adsorbed was shown immediately after. However, the methanol concentration at the outlet of the adsorption tower was C / C = 1.0 or more together with the adsorption of moisture, indicating a phenomenon that it was concentrated and desorbed. Thereafter, when water was saturated and adsorbed, methanol was not adsorbed and the inlet concentration and outlet concentration became equal.

  That is, a phenomenon that methanol seems to simply pass through the A-type honeycomb layer was observed. That is, based on the fact that the amount of methanol adsorbed and the amount of methanol desorbed are almost equal, it can be estimated that methanol and moisture were exchanged and adsorbed. This fact has already been confirmed in the material of Noritz (Netherlands), a manufacturer of mesoporous activated carbon (Noritt technical report TB 33 / 08-95: NORIT activated carbon filter medium and its device). As for desorption, as a result of experiments, it was found that more than half of the amount of adsorbed moisture was desorbed only by flowing nitrogen gas.

  Therefore, as a comparative example, it has been clarified that almost all of the adsorbed moisture amount is desorbed by flowing hot air gas of about 60 ° C. instead of nitrogen in a contact time of about 2 seconds with the honeycomb layer. Presumably, if a vacuum pump is used in combination with warm air, desorption at room temperature is possible. Next, as described in the section “Means for Solving the Problems”, the ethyl acetate or methanol released from the top of the A system is repeatedly returned to the lower part of the B system adsorption layer and concentrated. Then, the processing is performed by the methods disclosed in various patents owned by the present inventors, and the details are omitted.

  In this way, a large amount of high-humidity exhaust gas containing water-soluble and dilute VOCs is treated by the above-mentioned means and by a novel method that is economically superior, thereby purifying the gas to zero emission. What can be done is not limited to dilute ethyl acetate and methanol, but can also be applied to the concentration and separation of bioethanol that could only be separated by distillation or permeable membrane methods. The dehumidifying effect of the living space can also be expected. As is known, the “Act on the Improvement of Management and Management of the Release of Specific Chemical Substances into the Environment”, the so-called “PRTR Law”, which is decided to be implemented after April 2002 (April 2002) However, it is not the regulation of emission concentration that has been conventionally practiced, but the regulation of the total emission amount of the whole factory, and as described above, it cannot be discharged after being diluted to a large amount of air during aeration. In view of such a situation, the present inventors treated the exhaust gas containing VOC with a new adsorbent different from the conventional one, and alcohols mixed in the exhaust gas. Therefore, it is an epoch-making invention as a technology for preventing global warming gas, and can fully meet social needs.

DESCRIPTION OF SYMBOLS 1 ... Raw material exhaust gas supply line 1A, 1B ... Adsorption tower 4 ... Vacuum pump 5 ... Cooler 6 ... Collected liquid take-out line 7 ... Uncondensed gas return line 9A ... Purge gas supply line

Claims (4)

A high-concentration water-containing exhaust gas containing water-soluble volatile hydrocarbons in one adsorbing device, consisting of a layer filled with zeolite honeycomb, commonly known as molecular sieve adsorbent, and performing adsorption and desorption alternately. And adsorbs the moisture by adsorbing the adsorbent layer in the adsorbing device and releasing the water-soluble volatile hydrocarbons from the outlet of the adsorbing device while switching the other adsorbing device to desorption. In the processing method consisting of taking out the released water out of the system and releasing it outdoors,
A pre-stage filled with a honeycomb layer formed from zeolite having a pore diameter of 3 mm and / or a hydrophobic silica gel honeycomb layer before the adsorbing apparatus, and a post-stage filled with granular or honeycomb mesoporous activated carbon and / or hydrophobic silica gel A method for treating exhaust gas containing dilute water-soluble hydrocarbons and containing a large amount of water, using the adsorption device communicating with the latter stage.   The adsorption / desorption means of the adsorption / desorption device is configured to inject hot air or nitrogen at a room temperature from the top of the adsorption device (previous stage) and / or suck it using a vacuum pump, and adjust the adsorption / desorption switching time. It is 1 to 30 minutes, and the obtained water is released out of the system, and water-soluble volatile hydrocarbons that do not contain moisture released from the previous stage during adsorption are returned to the subsequent adsorption apparatus and concentrated. 2. A method for treating exhaust gas containing a large amount of high-humidity water according to 1.   In the above method, the honeycomb used in the preceding stage is formed from a granular or powdery raw material (zeolite having a pore diameter of 3 mm) into a desired shape by using sepiolite, inorganic fibers, and / or colloidal silica. The method for treating exhaust gas containing a large amount of moisture at a high humidity according to any one of claims 1 and 2, wherein the material is obtained by firing after mixing with an organic binder.   The amount of water-soluble volatile hydrocarbons in the exhaust gas recovered after being treated by the above method is approximately 100%, and includes a large amount and a high amount of the diluted volatile hydrocarbons according to any one of claims 1, 2, and 3. An exhaust gas purification method containing moisture of humidity.

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