JPH09137932A - Method and apparatus for removing harmful component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accomplish adsorption of malodor and harmful components in an exhaust gas and a desorption/regeneration treatment of an adsorbent by a method wherein an adsorbent layer mounted in a reaction container moves freely among an adsorption zone, a desorption layer and a cooling zone to adsorb or desorb the harmful components and the harmful components are removed by catalytic combustion. SOLUTION: A reaction container 3 mounted in an adsorbent layer 4 is divided into an adsorption zone 5 to adsorb harmful components, a desorption zone 7 to desorb the harmful components and a cooling zone 6 not effecting adsorption or desorption. In the adsorption zone 5, the harmful components contained in an exhaust gas 1 is adsorbed by an adsorbent layer 4 comprising a heat resistant inorganic compound, in the desorption zone 7, the harmful components adsorbed undergoes a desorption by desorbing air 14 heated passing through the adsorption layer 4 to generate a gas containing the harmful components concentrated. The gas containing the harmful components concentrated is burned and removed in a catalytic layer 15 for combustion. In the cooling zone 6, the gas is passed through the adsorbent layer 4 again and discharged outside the system as disposed exhaust gas 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for adsorbing and desorbing malodorous and harmful components in exhaust gas and performing catalytic combustion to remove the harmful components, and particularly to the malodorous components and harmful components contained in the exhaust gas. The present invention relates to a method for removing harmful components, which combines adsorption and catalytic combustion suitable for removing components, and an apparatus for carrying out the method.

[0002]

2. Description of the Related Art Exhaust gas emitted from reaction processes such as chemical industry, exhaust gas from manufacturing processes (baking, drying, cleaning) of resins, plywood, semiconductors, etc. The exhaust gas that is generated contains a trace amount of offensive odor components and harmful components. In the chemical industry, decomposition gases of raw materials, organic acids such as carbon monoxide, hydrocarbons, acetic acid and the like, aldehydes and the like, which are unrecovered, are included as typical ones. The exhaust gas contains alcoholic aromatic hydrocarbons such as toluene and acetone which are used as a solvent in the manufacturing process of resins and the like, and in the painting process. Exhaust gas containing these components,
Since it emits a foul odor if it is exhausted as it is, and is harmful to humans, there is provided a treatment facility for deodorizing and detoxifying it before exhausting from the viewpoint of pollution prevention. As a conventional technique for treating the exhaust gas containing these bad odors and harmful components, there are treatment methods roughly classified into an adsorption method, an absorption method and a combustion oxidation method. The adsorption method among them is a method of removing silica gel, alumina gel, zeolite, clay minerals, activated carbon and the like by using the adsorption force. In addition, the absorption method is a method that utilizes the chemical reactivity (acid-base reaction, etc.) of the substance to be treated. Basic compounds such as ammonia and amines should be washed with an acid, and acidic mercaptans should be washed with an alkali. Cleaning is effectively used. Further, an aqueous solution of hypochlorous acid, chlorine, potassium permanganate or the like is a strong oxidant, and there is a method of absorbing and oxidatively decomposing using such an aqueous solution. Further, the combustion oxidation method is roughly classified into a direct combustion method and a catalytic combustion method. The direct combustion method is a method in which exhaust gas is generally heated using an auxiliary fuel, and the bad odor and harmful components in the exhaust gas are burned at a temperature of 800 ° C. or higher to produce carbon dioxide and water. The catalytic combustion method is a method of burning offensive odors and harmful components in exhaust gas at a relatively low temperature of 500 ° C. or lower due to the oxidizing action of the catalyst. These treatment methods are selected in consideration of the exhaust gas conditions and economic efficiency, but the adsorption method is suitable when the amount of the removal component in the exhaust gas is a minute amount (ppm or less), and if the amount of the removal component increases, Proportionately, the life will be shortened, and it will be necessary to regenerate or replace the adsorbent in a short time. Further, when the adsorbent is regenerated, the adsorbed removal component is desorbed and discharged, so that a removal treatment in a downstream is required. The absorption method is not suitable for treating exhaust gas containing different types of removal components because the absorption liquid to be used has selectivity, and also requires post-treatment of the absorption liquid and waste water. For these reasons, the combustion oxidation method has been widely adopted as a method for removing malodors and harmful components. Recently, the catalytic combustion method is considered to be a cause of saving auxiliary fuel and secondary pollution as compared with the direct combustion method. Since it has advantages such as no generation of NOx, it has come to be noticed and adopted. FIG. 2 is a flow chart showing an example of a catalytic combustion method in the conventional technique. In the figure, the exhaust gas 1 sucked by the exhaust gas fan 2 (when the exhaust gas 1 is introduced in a pressurized state, the exhaust gas fan 2 may not be necessary),
Enter the heat exchanger 17. In the heat exchanger 17, the exhaust gas 1 is heated by heat exchange with its own combustion treatment exhaust gas 16 and becomes preheated exhaust gas 18 and is guided to the catalytic combustion furnace 19. In the upstream of the catalytic combustion furnace 19, the preheated exhaust gas 18 at the time of starting the apparatus is
Burner 1 for preheating (heating) and backup heating when the heat exchanger 17 does not heat to the required temperature
An exhaust gas preheating device 24 having zero is provided. In the case of this catalytic combustion type exhaust gas treatment device, the combustion catalyst layer 1
It is necessary to preheat the preheated exhaust gas 18 to the ignition temperature of the combustion catalyst layer 15 according to the components in the preheated exhaust gas 18 at the inlet of No. 5, and the combustion catalyst layer 15 is activated for the first time to start catalytic combustion. The preheating temperature of the preheating exhaust gas 18 is approximately 150 to 400 ° C., and the auxiliary combustion burner 10 of the exhaust gas preheating device 24 in which the heat exchanger 17 and the exhaust gas preheating device 24 are responsible for preheating the preheating exhaust gas 18 is the auxiliary fuel 11. Air 13 is supplied by the combustion air fan 12 to form a flame by gas phase combustion to preheat the preheated exhaust gas 18. As the auxiliary fuel 11, LPG, natural gas, city gas or high-quality oil such as light oil or kerosene is used. A catalyst layer 15 for combustion is provided in the catalytic combustion furnace 19, and when the preheated exhaust gas 18 passes through the catalyst layer 15 for combustion, it burns offensive odor components and harmful components at a low temperature due to the oxidizing action of the catalyst, thus causing no pollution. The exhaust gas 1 becomes exhaust gas 16 by the heat exchanger 17 and is exhausted 21 from the chimney 20 after being recovered by the exhaust heat recovery device 25 in the subsequent flow. The inlet preheating temperature of the combustion catalyst layer 15 is controlled by adjusting the amount of the auxiliary fuel 11 by the control valve 23 by the temperature controller 22 at the inlet of the combustion catalyst layer 15 and adjusting the combustion amount of the auxiliary combustion burner 10. This catalytic combustion method can reduce the amount of the auxiliary fuel 11 as compared with the direct combustion method, but it is necessary to heat all the exhaust gas passing through the combustion catalyst layer 15 to the ignition temperature of the removed component or more, and thus the large capacity is required. In the case of exhaust gas, the burden of the auxiliary fuel 11 on the operating cost cannot be said to be small. Therefore, measures such as installing the heat exchanger 17 and heating the preheated exhaust gas 18 on the catalyst inlet side by the combustion heat of the exhaust gas to reduce the consumption of the auxiliary fuel 11 during operation have been taken.
However, this heat exchanger 17 also exhibits a sufficient effect when the ratio of the removed components in the exhaust gas is relatively large and the temperature increase due to combustion can be expected to be 100 ° C. or more. Some offensive odors and harmful components, such as ammonia, amines, aldehydes, and thiols, have a strong odor even if they are contained in a very small amount (ppm or less). Preheated exhaust gas 1 containing a small amount of these
In the case of 8, since the temperature rise due to combustion can hardly be expected, the effect of heating the exhaust gas by the heat exchanger 17 is small. The preheated exhaust gas 18 containing a trace amount of this odor and harmful components,
As a method of reducing the consumption amount of the auxiliary fuel 11 and efficiently treating it, heat resistance is provided in the preceding stage in a flue or a pipe through which exhaust gas containing a bad odor or harmful components such as ammonia, amines, aldehydes and thiols flows. Volatile inorganic adsorbent, a combustion catalyst is placed in the latter part, and the adsorbent in the first part adsorbs the malodorous and harmful components to concentrate it, and then the adsorbent is heated to desorb the malodorous and harmful components and the concentration. It is a method of removing harmful components with a high degree of combustion by a combustion catalyst in the latter stage,
Since it is regenerated and heated by utilizing the heat of the combustion catalyst in the latter stage, it is excellent in economic efficiency, and the adsorbent and the heat exchanger are integrated to make the apparatus compact. Examples of the heat-resistant inorganic adsorbent include alumina, silica, silica-alumina, magnesia, various clay minerals and zeolites, and those having a large specific surface area and a large adsorption capacity are used. Further, as the combustion catalyst, a catalyst in which a precious metal such as platinum or palladium and / or a base metal such as manganese, iron, cobalt or copper is supported on alumina is used. FIG. 3 is a flow showing an example of a deodorizing device of a system in which an adsorption method and a catalytic combustion method are combined. The deodorizing device includes a heat-resistant inorganic adsorbent layer 4, which is integrated with the heat exchanger 17, an exhaust gas preheating device 24, and a combustion catalyst layer 15. The exhaust gas 1 containing a foul odor and a harmful component is introduced into the adsorbent layer 4. Before the adsorbent layer 4 reaches the saturated adsorption state, the exhaust gas preheating device 24 having the auxiliary burner 10 is provided.
Is started to heat the combustion catalyst layer 15 to raise the temperature to a temperature at which the combustion catalyst layer 15 is activated and acts. The waste heat of the combustion catalyst layer 15 is transferred to the adsorbent layer 4 via the heat exchanger 17. The malodorous substance desorbed by the temperature rise of the adsorbent layer 4 is burned and removed by the combustion catalyst layer 15. The adsorbent layer 4 is integrated with the heat exchanger 17. The exhaust gas preheating device 24 does not always start up, but the exhaust gas 1 is passed through the heat-resistant inorganic adsorbent layer 4 to adsorb and remove the malodorous and harmful components in the exhaust gas 1, and exhaust through the heat exchanger 17. The heating and desorption treatment of the heat-resistant inorganic adsorbent layer 4 is to start the exhaust gas preheating device 24 only when the adsorbent layer 4 approaches the saturated adsorption state.

[0003]

The above-mentioned prior art uses the auxiliary fuel only during the desorption operation due to the combination of the heat-resistant inorganic adsorbent layer in the former stage and the combustion catalyst layer in the latter stage. The amount can be reduced significantly. But,
Even during the desorption operation, the bad odor, because the exhaust gas containing the harmful components is supplied to the adsorbent layer, it does not lead to the reduction of the exhaust gas amount for burning and removing the harmful components, the combustion catalyst layer of the latter stage,
The amount of catalyst required is the same as in the case of the catalytic combustion system, and the adsorbent layer also requires a large volume of the same amount or about ½, which does not lead to reduction of the amount of catalyst and adsorbent. Further, there is a problem that it is difficult to judge the time of desorption treatment by heating the adsorbent layer because the time until the saturated state of the adsorbent is changed due to the foul odor in the exhaust gas and the change in the content ratio of the harmful component. .

An object of the present invention is to solve the above-mentioned problems in the prior art. At the same time, the adsorption of malodorous and harmful components in exhaust gas and the desorption / regeneration treatment of the adsorbent which has reached a saturated adsorption state are carried out simultaneously. It can be carried out continuously, and can remove the small amount of deodorized and high-concentration malodor and harmful components effectively by combustion with a small combustion catalyst layer. It is an object of the present invention to provide a method for removing harmful components in exhaust gas, which can be continuously carried out simultaneously with desorption and catalytic combustion, and a device for removing harmful components with a compact structure, which is inexpensive and inexpensive to maintain.

[0005]

The method and apparatus for removing harmful components of the present invention basically comprises a reaction vessel containing a heat-resistant inorganic adsorbent layer and an adsorption zone for adsorbing malodorous and harmful components. A desorption zone for desorbing the components, and a cooling zone that is neither adsorbed nor desorbed between the adsorption zone and the desorption zone, and further, the adsorption zone is surrounded by the desorption zone through the cooling zone. None, again
The adsorbent layer has a structure in which the harmful components adsorbed to the adsorbent layer move at least from the adsorption zone to the desorption zone, and reciprocate between the adsorption and desorption zones between the zones, and the desorption gas flow The combustion catalyst layer is arranged only in the wake of the passage. In order to achieve the above-mentioned object of the present invention, the present invention is specifically configured as described in the claims. That is, the present invention relates to claim 1.
As described in 1, the ammonia, amines, aldehydes, thiols, and other malodorous and harmful components contained in the exhaust gas are adsorbed by the adsorbent layer, the adsorbed harmful components are desorbed, and then removed by catalytic combustion. In the method, the reaction vessel containing the adsorbent layer is cooled without adsorption or desorption between the adsorption zone for adsorbing harmful components, the desorption zone for desorbing harmful components, and the adsorption zone and desorption zone. A method of adsorbing or desorbing the harmful components by catalytically burning and removing the desorbed harmful components, wherein the adsorbent layer is configured to be freely movable between the zones. The step of adsorbing the harmful components contained in the exhaust gas with the adsorbent layer made of a heat-resistant inorganic material and the harmful components adsorbed by the adsorbent layer with heated air or a predetermined gas. Desorbed by the steps of generating a gas containing concentrated harmful components, a step of burning off the combustion catalyst layer desorption gas containing harmful components is the concentration,
This is a method of removing harmful components at least continuously. In this way, one adsorbent layer is roughly divided into an adsorption part and a desorption part, and an operation of adsorbing a dilute concentration of harmful components near the saturation concentration with a heat-resistant inorganic adsorbent layer, and a relatively small amount of this The desorption with the heated air (gas) to generate the air (gas) containing a high concentration of harmful components and the catalytic combustion can be performed separately from the adsorption of the harmful components in the exhaust gas. The amount of adsorbent used for (or adsorption) may be 1/2 or less (several% to 50% or less) of the total amount of adsorbent, and desorption air (gas) may be small, so the cost and maintenance of the device The cost will be low. Further, since the cooling zone is provided, the adsorbent layer heated in the desorption zone is
Since it is sufficiently cooled in the cooling zone, harmful components are sufficiently adsorbed in the adsorption zone, and there is an effect that a bad odor in exhaust gas and leakage of harmful components do not occur. Further, according to the present invention, as described in claim 2, an adsorbent layer made of a heat-resistant inorganic material for adsorbing and concentrating the harmful components is provided in a flue or a pipe through which exhaust gas containing a malodorous or harmful component flows. A device for removing harmful components, which heats the adsorbent layer to desorb the adsorbed harmful components, and burns and removes the adsorbent layers in a downstream catalyst layer for combustion, wherein An adsorption zone for adsorbing harmful components, and a desorption zone for desorbing the harmful components,
Further, between the adsorption zone and the desorption zone, it is divided into a cooling zone which does not adsorb or desorb, and the adsorbent layer is structured to be freely movable between the zones to remove the desorbed harmful components. A device for removing harmful components, which comprises at least a combustion catalyst layer for catalytic combustion. With such a structure, it is possible to effectively realize the method of removing harmful components described in claim 1, and obtain a high-performance device for removing harmful components that is inexpensive and has low maintenance cost. Further, according to the present invention, as described in claim 3,
In the second aspect, the reaction vessel containing the adsorbent layer is an apparatus for removing harmful components in which the adsorption zone is surrounded by the desorption zone via the cooling zone. With such a structure, since the adsorbent layer heated in the desorption zone is sufficiently cooled in the cooling zone, no harmful component leaks in the adsorption zone, and the common effect of the above-mentioned claim 2 is obtained. In addition, an inexpensive and highly reliable device for removing harmful components can be obtained. Further, according to the present invention, as described in claim 4, in claim 2, the adsorbent layer is desorbed between the respective zones of the reaction vessel containing the adsorbent layer, at least the adsorbent layer having adsorbed harmful components. This is a device for removing harmful components, which has a structure of moving to the zone and moving the adsorbent layer back and forth between the adsorption zone and the desorption zone. With such a structure, harmful components in the exhaust gas can be sufficiently adsorbed by the adsorbent layer in the adsorption zone and can be reliably moved to the desorption zone for desorption operation. In addition to the common effects of, it is possible to realize a highly reliable device for removing harmful components. Further, according to the present invention, as described in claim 5, in any one of claims 2 to 4, only the adsorbent layer adsorbing the harmful component located in the desorption zone is heated to concentrate the harmful component. After desorption in such a state, the catalyst layer for combustion is disposed only in the downstream of the desorption gas flow path to provide a harmful component removing device that burns and removes harmful components. With such a structure, only the adsorbent layer that has adsorbed harmful components can be heated to generate a relatively small amount of desorbed gas containing high concentration of harmful components, and the combustion catalyst can be effectively removed with less combustion catalyst. Since it is possible to obtain a high-temperature purified gas, it is possible to use this as a part of the desorption gas. A removal device is obtained. Also,
According to a sixth aspect of the present invention, in any one of the second to fifth aspects, the present invention provides a harmful component removing device including means for continuously adsorbing, desorbing, and burning and removing. is there. In this way, by performing continuous adsorption, desorption and catalytic combustion removal, the harmful components are effectively adsorbed, desorbed and catalytically burned with relatively few adsorbent layers and combustion catalyst layers. Therefore, in addition to the common effect of claim 2, it is possible to realize a device for removing harmful components that is compact, inexpensive, and low in maintenance cost.

The reaction vessel containing the adsorbent layer of the present invention is
It is divided into an adsorption zone, a desorption zone, and a cooling zone that is neither adsorbed nor desorbed, and the heat-resistant inorganic adsorbent layer reciprocates between the above-mentioned zones, at least from the adsorption zone to the desorption zone. The adsorbent layer located in the adsorption zone can condense offensive odors and harmful components by the passage of exhaust gas by adsorption, and the portion of the adsorbent layer that has adsorbed this harmful component is moved to the desorption zone by reciprocating movement. By heating desorbed air (which may be purified exhaust gas, gas such as nitrogen), the absorbed and concentrated malodor and harmful components are desorbed, and a desorbed gas containing a high concentration of harmful components is obtained. The odor and harmful components can be burned and removed by a combustion catalyst arranged in the latter stage of the desorption zone. Then, the desorbed portion of the adsorbent layer returns to the adsorption zone by reciprocating movement again to adsorb and concentrate the removed component in the exhaust gas. As a result, there is an advantage in that the malodor and harmful components in the exhaust gas can be removed by adsorption and the adsorbent desorption / regeneration process can be continuously performed at the same time. Further, the desorption zone may be several% to 50% or less of the entire adsorbent layer, and desorption operation can be performed by separating from the adsorption of harmful components in the exhaust gas. Therefore, a very small amount will suffice, and the amount of combustion catalyst will be small. Furthermore, the adsorption zone has a structure in which a desorption zone is provided via a cooling zone, so that the adsorbent layer heated in the desorption zone is sufficiently cooled in the cooling zone, and thus malodor and harmful components are adsorbed and removed. It will not leak without it.

[0007]

1 (a) and 1 (b) are schematic views showing the structure of a harmful component removing apparatus, which is an example of an embodiment of the present invention, and FIG. FIG. 1A is a sectional view taken along the line A-A of FIG. In the figure, the exhaust gas 1 sucked by the exhaust gas fan 2 (the exhaust gas fan 2 may be unnecessary when the exhaust gas 1 is introduced in a required pressurization state) is the adsorption of the reaction vessel 3 containing the adsorbent layer. Introduced into Zone 5. The heat-resistant inorganic adsorbent 4 in the reaction vessel 3 having the adsorbent layer inside is structured to be capable of reciprocating movement, and the piston 9 together with the heat-resistant inorganic adsorbent layer 4 is controlled by controlling hydraulic pressure or air pressure. Move back and forth. The exhaust gas 1 introduced into the reaction vessel 3 containing the adsorbent layer is
When passing through the adsorbent layer 4, the malodorous and harmful components in the exhaust gas 1 are adsorbed. The exhaust gas 1 that has been purified by passing through the heat-resistant inorganic adsorbent layer 4 is introduced into the cooling zone 6, passes through the adsorbent layer 4 located in the cooling zone 6 again, and is discharged outside the system as the treated exhaust gas 8. It On the other hand, an exhaust gas preheating device 24 having an auxiliary combustion burner 10 is installed in the desorption zone 7, and the auxiliary fuel 11 and the air 13 from the combustion air fan 12 are provided.
Is constantly supplied with desorption air 14 capable of heating the adsorbent layer 4 to a required temperature by burning the adsorbent layer 4 with the auxiliary combustion burner 10. The adsorbent layer 4 that has adsorbed the malodorous and harmful components in the adsorption zone 5 moves into the desorption zone 7 and is heated by the desorption air 14. The heated adsorbent layer 4 is the adsorbent layer 4
The deodorizing air 14 passing through the
The harmful components are desorbed and separated and exhausted from the adsorbent layer 4. A combustion catalyst layer 15 is provided in the downstream of the desorption zone 7, and the desorption air 14 containing harmful components is used for the combustion catalyst 1
When passing through 5, the odorous components and harmful components are burned at a relatively low temperature due to the oxidizing action of the catalyst, and the purified combustion treatment exhaust gas 16 is discharged to the outside of the system. In the desorption zone 7, the bad odor and harmful components are desorbed, and the regenerated adsorbent layer 4 moves and enters the adsorption zone 5 again to adsorb the bad odor and harmful components in the exhaust gas 1 again. The adsorbent layer 4 has a structure in which the above-described adsorption and desorption operations are repeated for the entire area where adsorption and desorption are performed. The structure of the device for removing harmful components is such that the reaction vessel 3 containing the adsorbent layer is composed of an adsorption zone 5, a desorption zone 7, and a cooling zone 6 between the adsorption zone 5 and the desorption zone 7. Through the cooling zone,
It has a structure surrounding the adsorption zone 5. In addition, the heat-resistant inorganic adsorbent layer 4 in the reaction vessel 3 containing the adsorbent layer
Is provided with a piston 9 so as to be able to reciprocate, and moves the adsorbent layer 4 using hydraulic pressure or air pressure. At this time, the adsorbent layer 4 has a structure capable of moving the malodorous and harmful components adsorbed by the adsorbent layer 4 at least in the adsorption zone 5 to the desorption zone 7 between the respective zones. With this structure, the malodorous and harmful components adsorbed and concentrated on the adsorbent layer 4 in the adsorption zone 5 always move to the desorption zone 7, and the desorption air 14 causes the adsorbent layer 4 to desorb.
The offensive odor and harmful components are desorbed. Further, by providing the cooling zone 6 between the adsorption zone 5 and the desorption zone 7, when the adsorbent layer 4 heated in the desorption zone 7 moves, it is cooled by the treated exhaust gas 8 passing through the cooling zone 6. Is
When it moves to the adsorption zone 5, it is sufficiently cooled to a temperature at which it can adsorb malodorous and harmful components. That is, since the treated exhaust gas 8 passes through the cooling zone 6, no bad odor or leakage of harmful components from this region occurs. further,
By enabling the reciprocating movement of the adsorbent layer 4 by the piston 9, the adsorption and removal of the malodor and harmful components in the exhaust gas 1 and the desorption / regeneration process of the adsorbent layer that has adsorbed the malodor and harmful components and is close to the saturated adsorption state. And can be performed continuously at the same time. On the other hand, when the odor and harmful components are desorbed, the flow path is different from the flow path of the treated exhaust gas 8. Therefore, the amount of desorbed air is smaller than the exhaust gas amount, and the combustion catalyst layer 15
It requires less capacity. Further, since a bad odor and a high concentration of desorption gas of harmful components are generated from the adsorbent layer 4 in the desorption zone 7, the combustion treatment exhaust gas 16 after passing through the combustion catalyst layer 15 has a high temperature, so that a part of the desorption air 14 is generated. Can be reused as. According to the present invention, the reaction vessel containing the adsorbent layer is divided into an adsorption zone, a desorption zone, and a cooling zone, and / or by moving the adsorbent layer back and forth, a bad odor in the exhaust gas, harmful Adsorption and removal of components, and desorption / regeneration processing of the adsorbent layer that has adsorbed a malodorous or harmful component and is close to a saturated adsorption state can be simultaneously performed continuously. In addition, since desorption can be performed separately from adsorption of exhaust gas, desorption air can be significantly smaller than the amount of exhaust gas, and the capacity of the combustion catalyst can be small. 16 becomes hot,
It can be reused as part of the desorption air 14.

[0008]

According to the present invention, as described in claim 1, the odorous and harmful components such as ammonia, amines, aldehydes or thiols contained in the exhaust gas are adsorbed by the adsorbent layer and adsorbed. After desorption of harmful components, in a method of removing by catalytic combustion, a reaction vessel containing an adsorbent layer, an adsorption zone for adsorbing harmful components, a desorption zone for desorbing harmful components, the adsorption zone and desorption zone In the meantime, it is divided into a cooling zone that does not adsorb or desorb, and the adsorbent layer is configured to be freely movable between the above-mentioned zones to adsorb or desorb the harmful components and remove the desorbed harmful components. It is a method of burning the catalyst to remove it. In this way, one adsorbent layer is roughly divided into an adsorption part and a desorption part, and an operation of adsorbing a dilute concentration of harmful components near the saturation concentration with a heat-resistant inorganic adsorbent layer, and a relatively small amount of this The desorption with the heated air (gas) to generate the air (gas) containing a high concentration of harmful components and the catalytic combustion can be performed separately from the adsorption of the harmful components in the exhaust gas. The amount of adsorbent used for (or adsorption) may be 1/2 or less (several% to 50% or less) of the total amount of adsorbent, and desorption air (gas) may be small, so the cost and maintenance of the device The cost is low, and since the cooling zone is provided, the adsorbent layer heated in the desorption zone is sufficiently cooled in the cooling zone, so that the harmful components are sufficiently adsorbed in the adsorption zone, and the odor and odor in the exhaust gas Has the effect of not leaking components Further, according to the present invention, as described in claim 2, an adsorbent layer made of a heat-resistant inorganic material for adsorbing and concentrating the harmful components is provided in a flue or a pipe through which exhaust gas containing a malodorous or harmful component flows. A device for removing harmful components that desorbs and removes the harmful components adsorbed to the adsorbent layer and burns them with a downstream catalyst for combustion to remove the harmful components from the reaction vessel containing the adsorbent layer. The adsorption zone for adsorbing, the desorption zone for desorbing the harmful components, and further between the adsorption zone and the desorption zone, divided into a cooling zone not adsorbed or desorbed, the adsorbent layer between the respective zones. An apparatus for removing harmful components, which is structured to be freely movable and has at least a catalyst layer for burning the desorbed harmful components. With such a structure, the method for removing harmful components described in claim 1 can be effectively realized, and a high-performance device for removing harmful components that is inexpensive and has low maintenance costs can be obtained. Further, according to the present invention as set forth in claim 3, in claim 2, the reaction vessel having an adsorbent layer therein has a structure in which an adsorption zone is surrounded by a desorption zone via a cooling zone. It is what With such a structure, since the adsorbent layer heated in the desorption zone is sufficiently cooled in the cooling zone, no harmful component leaks in the adsorption zone, and the common effect of the above-mentioned claim 2 is obtained. In addition, an inexpensive and highly reliable device for removing harmful components can be obtained. Further, according to the present invention, as described in claim 4, in claim 2, the adsorbent layer is desorbed between the zones of the reaction vessel containing the adsorbent layer, at least the adsorbent layer having adsorbed harmful components. The adsorbent layer moves to the zone, and the adsorbent layer is a device for removing harmful components having a structure of reciprocating between the adsorption zone and the desorption zone. By adopting such a structure,
In the adsorption zone, the harmful components in the exhaust gas can be sufficiently adsorbed by the adsorbent layer, and the adsorbent layer can be reliably moved to the desorption zone to perform the desorption operation. It is possible to realize a device for removing harmful components having high properties. Further, according to the present invention, as described in claim 5,
In any one of Claims 2 thru | or 4, only the adsorbent layer which adsorbed the harmful component located in the desorption zone is heated, and after desorbing in the state which concentrated the harmful component, the desorption gas flow path wake A combustion catalyst layer is provided only on the above to form a harmful component removing device that burns and removes harmful components. With such a structure, only the adsorbent layer that has adsorbed harmful components can be heated to generate a relatively small amount of desorbed gas containing high concentration of harmful components, and the combustion catalyst can be effectively removed with less combustion catalyst. Since it is possible to obtain a high-temperature purified gas, it becomes possible to use this as a part of the desorption gas, and in addition to the common effect of the above-mentioned claim 2, the removal of harmful components which are inexpensive and inexpensive to maintain The device is obtained. Further, as described in claim 6, the present invention provides the harmful component removing device according to any one of claims 2 to 5, which comprises means for continuously performing adsorption, desorption and combustion removal. It is a thing. In this way, by carrying out continuous adsorption, desorption, and catalytic combustion removal, it is possible to effectively remove harmful components by adsorption, desorption, and catalytic combustion with a relatively small amount of adsorbent layer and combustion catalyst layer. Is possible,
In addition to the common effects of the second aspect, it is possible to realize a compact, inexpensive, low maintenance cost harmful substance removing device. The reaction vessel containing the adsorbent layer of the present invention is divided into an adsorption zone, a desorption zone, and a cooling zone that is neither adsorbed nor desorbed, and the heat-resistant inorganic adsorbent layer is at least between the zones. Since it moves back and forth between the adsorption zone and the desorption zone, the adsorbent layer located in the adsorption zone can condense offensive odors and harmful components by adsorption of exhaust gas. When the layer part is moved to the desorption zone by reciprocating movement, the heated desorption air (purified exhaust gas, gas such as nitrogen may be adsorbed and concentrated odor, harmful components are desorbed, and high concentration of harmful components A desorption gas containing is obtained. The odor and harmful components can be burned and removed by a combustion catalyst arranged in the latter stage of the desorption zone. Then, the desorbed portion of the adsorbent layer returns to the adsorption zone by reciprocating movement again to adsorb and concentrate the removed component in the exhaust gas. As a result, there is an advantage that the bad odor and harmful components in the exhaust gas can be removed by adsorption and the adsorbent desorption / regeneration process can be continuously performed simultaneously. Further, the desorption zone may be several% to 50% or less of the whole adsorbent layer, and the desorption operation can be performed separately from the adsorption of harmful components in the exhaust gas, so the desorption air (gas) is the amount of exhaust gas to be treated. Compared with the above, a very small amount will be sufficient, and the amount of the combustion catalyst will be small. In addition, the adsorption zone has a structure in which a desorption zone is provided via a cooling zone, so that the adsorbent layer heated in the desorption zone is sufficiently cooled in the cooling zone, and the odor and harmful odor in the adsorption zone are reduced. The components will not leak without being absorbed and removed.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a configuration of a harmful component removing device exemplified in an embodiment of the present invention.

FIG. 2 is a schematic diagram showing an example of the configuration of a conventional catalytic combustion type deodorizing device.

FIG. 3 is a schematic diagram showing an example of the configuration of a conventional deodorizing device that combines adsorption and catalytic combustion.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Exhaust gas 2 ... Exhaust gas fan 3 ... Reaction container containing an adsorbent layer 4 ... Heat-resistant inorganic adsorbent layer 5 ... Adsorption zone 6 ... Cooling zone 7 ... Desorption zone 8 ... Treatment exhaust gas 9 ... Piston 10 ... Combustion burner 11 ... auxiliary fuel 12 ... combustion air fan 13 ... air 14 ... desorption air 15 ... combustion catalyst layer 16 ... combustion processing exhaust gas 17 ... heat exchanger 18 ... preheating exhaust gas 19 ... catalytic combustion furnace 20 ... chimney 21 ... exhaust 22 ... temperature control Total 23 ... Control valve 24 ... Exhaust gas preheating device 25 ... Waste heat recovery device

Claims (6)

[Claims] 1. A odorous or harmful component such as ammonia, amines, aldehydes or thiols contained in exhaust gas is adsorbed by an adsorbent layer, and the adsorbed harmful component is desorbed and then removed by catalytic combustion. In the method, a reaction vessel containing an adsorbent layer is provided with an adsorption zone for adsorbing harmful components, a desorption zone for desorbing harmful components, and a cooling zone for performing no adsorption or desorption between the adsorption zone and the desorption zone. And a method in which the adsorbent layer is configured to be freely movable between the respective zones to adsorb or desorb the harmful components in the exhaust gas, and to catalytically remove the desorbed harmful components. A step of adsorbing a harmful component contained in the exhaust gas by an adsorbent layer made of a heat-resistant inorganic material, a harmful component adsorbed by the adsorbent layer, heated air or a predetermined amount. And a step of generating a gas containing a concentrated harmful component by desorption with a gas and a step of burning and removing the desorbed gas containing the concentrated harmful component by a combustion catalyst layer at least continuously. How to remove harmful components. 2. A heat-resistant inorganic adsorbent layer for adsorbing and concentrating harmful components in exhaust gas is installed in a flue or pipe through which exhaust gas containing malodorous and harmful components flows, and the adsorbent layer is provided with the adsorbent layer. A device for removing harmful components that desorbs adsorbed harmful components and burns with a downstream catalyst for combustion to remove the adsorbent layer, a reaction container having an adsorbent zone for adsorbing the harmful components, Desorption zone for desorbing harmful components, further between the adsorption zone and the desorption zone, divided into a cooling zone that also does not adsorb or desorb, the adsorbent layer with a structure that can move freely between the above zones, A device for removing harmful components, comprising at least a catalyst layer for burning and removing the desorbed harmful components. 3. The apparatus for removing harmful components according to claim 2, wherein the reaction vessel containing the adsorbent layer has a structure in which the adsorption zone is surrounded by a desorption zone through a cooling zone. 4. The adsorbent layer according to claim 2, wherein the adsorbent layer having at least harmful components adsorbed therein can be moved to the desorption zone between the zones of the reaction vessel containing the adsorbent layer. The adsorbent layer has a structure in which it reciprocates freely between the adsorption zone and the desorption zone. 5. The desorption gas according to any one of claims 2 to 4, wherein only the adsorbent layer adsorbing the harmful component located in the desorption zone is heated to generate a desorbed gas containing the harmful component in a high concentration. After that, a device for removing harmful components is provided, in which a catalyst layer for combustion is installed only in the wake of the desorption gas flow path, and means for burning and removing harmful components is provided. 6. A device for removing harmful components according to any one of claims 2 to 5, further comprising means for continuously performing adsorption, desorption, and combustion removal by a catalyst.