JPH10244130A - Air purifying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the subject device capable of executing the most suitable purifying treatment corresponding to a component in air to be treated. SOLUTION: In the device, when a waste gas concn. higher than a prescribed value is detected by an upstream waste gas sensor 62, the waste gas relatively high in concn. is purified efficiently by heating a photocatalyst filter 30 and an oxidation catalyst filter 32 with a halogen lump 57 to increase the activity. On the other hand, when the waste gas concn. lower than the prescribed value is detected with the upstream waste gas sensor 62, the air is purified efficiently with an adsorption filter 34 by stopping heating with the halogen lump 57 to keep at a normal temp. In this way, the most suitable purifying treatment is executed corresponding to the component in the air to be treated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air purifying apparatus for purifying odorous and harmful components in air.

[0002]

2. Description of the Related Art An air purifying apparatus for purifying air by accommodating activated carbon or the like in a cartridge and forcing the air into the cartridge has been put to practical use. Here, since the adsorbent such as activated carbon is of a disposable type, it is necessary to exchange the adsorbent at a high frequency, which is uneconomical. In addition, if the exchange time is delayed, the air cannot be properly purified.

On the other hand, when an air purifier is installed in an automobile, when traveling in an area where there are many traveling vehicles, a large amount of NOx, CO, odor components and the like discharged from other vehicles enter the interior of the automobile. Not only has the frequency of replacement of the adsorbent increased, but the harmful components in the air have not been sufficiently removed and introduced into the vehicle.

[0004] The applicant of the present invention irradiates a filter composed of an adsorbent such as activated carbon and a photocatalyst with ultraviolet rays for the purpose of removing odors in the air, and adsorbs odor components such as NOX using the adsorbent. An air purification device for automobiles, which oxidizes and decomposes odor components, particularly tobacco odor main components (aldehyde and ammonia), which is difficult to adsorb with the adsorbent, by the photocatalyst to efficiently remove odor components in the air. , Japanese Patent Application 8
No. 93636.

Here, the photocatalyst has an action of oxidizing NO, which is hardly adsorbed by activated carbon, to NOX, which is easily adsorbed by activated carbon. Further, the NOx adsorbed on the photocatalyst is further oxidized and decomposed into a substance such as HNO3, so that the rate of accumulation of NOX on the activated carbon is suppressed by supporting the photocatalyst.
In addition, the photocatalyst oxidizes and decomposes odor components (aldehyde, ammonia, etc.) other than NOX, so that the speed at which the harmful substances accumulate can be suppressed and the harmful substances once adsorbed by the adsorbent are also oxidized. Can be disassembled.

Further, in addition to the removal of NOx and odor components, the present applicant has also proposed the above-mentioned filter in which a photocatalyst is supported on an adsorbent, and Pd as an adsorbent for the purpose of removing CO by oxidation.
It has been proposed in Japanese Patent Application No. 8-153252 to use a filter carrying a CO oxidation catalyst comprising a white metal element. Further, the present applicant has disclosed a method of improving the NO removal performance by at least twice by applying heat as well as ultraviolet rays to the above-mentioned filter (Japanese Patent Application No. 8-31271).
Proposed in.

[0007]

However, in the method proposed heretofore, a photocatalyst is supported on an adsorbent or a mixture of a photocatalyst and an adsorbent is used, and the temperature suitable for the adsorbent is room temperature. Yes, for example, activated carbon fibers with the best adsorption performance can exhibit high performance at 20-30 ° C.

When the above-mentioned photocatalyst and CO oxidation catalyst are used at a high temperature (for example, 100 ° C.), harmful components (NO, CO, etc.) which are oxidized by the photocatalyst or CO oxidation catalyst, that is, exhaust gas components can be treated, but tobacco can be treated. Odor components containing odor cannot be adsorbed by an adsorbent such as activated carbon fiber. Therefore, when using a purification device consisting of a photocatalyst and an adsorbent,
In the method proposed by the present applicant, the temperature is reduced to a low temperature (normal temperature, for example, 20 to 30 ° C.) suitable for the adsorbent, and an air purification device containing a photocatalyst, a CO oxidation catalyst, and activated carbon fibers is used. . For this reason, the photocatalyst and the CO oxidation catalyst cannot be sufficiently activated, and the purification treatment has been performed in a state where the catalytic reaction rate is low.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an air purification apparatus capable of performing the most appropriate purification processing in accordance with components in the processing air. Is to do.

Another object of the present invention is to provide an air purification device capable of efficiently regenerating an oxidation catalyst and an adsorbent when purifying air using an oxidation catalyst and an adsorbent.

[0011]

In order to achieve the above object, an air purifying apparatus according to the present invention comprises an oxidation catalyst, an adsorbent disposed downstream of the oxidation catalyst, and an oxidation catalyst. An air purification device comprising: an oxidation catalyst heating unit for heating; and an oxidation catalyst heating control unit for controlling the heating intensity of the oxidation catalyst heating unit, wherein the oxidation catalyst heating control unit includes A heating intensity change command unit that sends a command to change the heating intensity, wherein the oxidation catalyst heating control unit receives a command from the heating intensity change command unit, and enhances the heating intensity of the oxidation catalyst heating unit. The technical feature is to regenerate the oxidation catalyst.

In order to achieve the above object, the air purifying apparatus according to claim 2 is characterized in that in claim 1, the oxidation catalyst heating means includes an ultraviolet irradiation means.

[0013] To achieve the above object, the air purifying apparatus according to the third aspect is characterized in that, in the first aspect, the oxidation catalyst contains a photocatalyst.

[0014] To achieve the above object, the air purifying apparatus according to claim 4 is characterized in that, in the air purifying apparatus according to claims 1 to 3, the adsorbent contains activated carbon.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments embodying the present invention will be described below with reference to the drawings. FIG. 1 shows a configuration of a vehicle air purification device 10 according to a first embodiment of the present invention, and FIG. 2 (A) shows a vehicle mounting position of the vehicle air purification device 10. As shown in FIG. 2A, the automotive air purification device 10 is housed on a trunk behind a vehicle cabin of a vehicle, and an exhaust pipe 18 extends to an air cleaner 72 of an engine 70. The automotive air purification device 10
Is provided with an intake pipe 12 for taking in the air in the vehicle compartment, and an outlet pipe 16 for blowing out the purified air into the vehicle compartment.

As shown in FIG. 1, an air purifying apparatus 10 for an automobile includes a turbo fan 42 for pumping air taken in from an intake pipe 12, a DC motor 40 for driving the turbo fan 42, and a DC motor A motor controller 44 for stopping and operating 40, a photocatalyst filter 30 for adsorbing and oxidizing exhaust gas components such as NO, an oxidation catalyst filter 32 for oxidizing CO in the air to CO2, and an adsorption filter 34 for adsorbing odor components. An ultraviolet lamp 58 for irradiating the photocatalyst filter 30 with ultraviolet light, a circuit 50 for turning on the ultraviolet lamp 58,
0, a halogen lamp 57 for heating the oxidation catalyst filter 32, a heating wire 46 for heating the adsorption filter 34, a temperature sensor 56 for measuring the temperature of the photocatalyst filter 30, and the air purification device 10. An upstream exhaust gas sensor 62 that measures the concentration of exhaust gas such as NO in the air taken in, and an upstream odor sensor 64 that measures the concentration of odor.
And a downstream exhaust gas sensor 66 for measuring the concentration of exhaust gas such as NO after being processed by the filter, a downstream odor sensor 68 for measuring the concentration of odor, the damper 22, the ultraviolet lamp 58 and the DC motor 40. Control device 54
Consisting of The damper 22 switches between an outlet pipe 16 for blowing air into the vehicle and an exhaust pipe 18 for sending exhaust to the engine.

The adsorption filter 34 is formed by folding activated carbon fibers into a pleated shape. That is, by folding the activated carbon fiber having a large area, the air passage speed is reduced, and the pressure loss is reduced. As this activated carbon fiber,
For example, Fine Guard (registered trademark) using acrylic fiber as a raw material provided by Toho Rayon Co., Ltd. can be used. As this fine guard, specific surface area of 500 to 12
00m 2 / g, average pore diameter 20 ~ 40mm, fiber diameter 7 ~
15 μm, fiber tensile strength 20-50 kg / mm 2, N content 2-10%, outer surface area 0.2-0.7 m 2 / g, benzene average adsorption 20-50% are provided. Here, FE-200 in which the fine guard is made into a felt shape is used. This activated carbon fiber has NO
In addition to adsorbing X, it strongly adsorbs odor components such as SOX and tobacco odor. The adsorption filter 34 is provided with NOX
When the performance deteriorates due to adsorption of the substance, the substance is heated by the built-in heating wire 46 and is regenerated by desorbing the substance to be adsorbed as described later.

The adsorption filter 34 of this embodiment is disposed downstream of the photocatalyst filter 30 and the oxidation catalyst filter 32 so that the photocatalyst filter 30 and the oxidation catalyst filter 32 are heated by a halogen lamp 57 and used for purification. Even at this time, the adsorption filter 34 can satisfactorily adsorb and remove substances oxidized by these catalysts without being heated. As the adsorption filter 34 continues its purification, its removal performance decreases due to accumulation of the substance to be adsorbed. For this reason, in the first embodiment, the adsorption filter 34 is regenerated by heating with the heating wire 46.

The oxidation catalyst filter 32 includes activated carbon fibers,
A noble metal catalyst such as Pd for oxidizing CO to CO2 is supported on a support such as alumina.

In the present embodiment, the oxidation catalyst filter 32 is disposed in close contact with or integrated with the photocatalyst filter 30, so that when the photocatalyst filter 30 is heated by the halogen lamp 57, the oxidation catalyst filter 32 is simultaneously heated. You. Therefore, even when the exhaust gas components of another vehicle from outside the vehicle invading into the vehicle at a high concentration, by heating the halogen lamp 57, a photocatalytic filter 30 NO _X was efficiently removed, efficiently CO in the oxidation catalyst filter 32 And the main components of the exhaust gas can be removed.

The photocatalyst filter 30 has a metal filter loaded with an adsorbent composed of activated carbon for adsorbing odor components and a photocatalyst for oxidizing and decomposing aldehydes and ammonia which are hardly adsorbed by activated carbon. I have. That is,
A photocatalyst is supported on the activated carbon. The filter is formed by laminating pleated stainless steel sheets. Here, a filter made of a stainless steel thin plate is used. However, instead of stainless steel, a filter obtained by folding a thin plate of copper, aluminum, etc. in a pleated shape can be used, and a thin plate of stainless steel, copper, aluminum, etc. can also be used. May be used in a honeycomb shape. Further, a photocatalyst obtained by kneading activated carbon into a photocatalyst and having a honeycomb shape may be used as the photocatalyst filter 30. By using a filter in which thin plates are folded in a pleated or honeycomb shape as a filter carrying the adsorbent,
The pressure loss is reduced, the surface area of the adsorbent is increased, and ultraviolet rays can be efficiently irradiated.

In the photocatalyst filter 30 of this embodiment, as described above, activated carbon for adsorbing exhaust gas components such as NOx and aldehydes, ammonia, etc., which are the main components of tobacco odor which is difficult to adsorb with activated carbon, are subjected to photocatalytic reaction. A photocatalyst is used which is oxidized and decomposed by water and eventually converted into water, carbon dioxide and nitric acid. This photocatalytic filter 30
It is placed about 5cm away from the halogen lamp 57,
By irradiating ultraviolet rays from the ultraviolet lamp 58 and heating by the halogen lamp 57 at the same time, the activity is increased.
_{In addition} to the above, it is possible to prevent deterioration due to accumulation of NO on the surface of the photocatalyst, which occurs when heating is not performed. Further, at the time of regeneration of the photocatalytic filter 30, the substance to be adsorbed is desorbed by heating to a relatively higher temperature than at the time of adsorption.

The photocatalyst oxidizes and decomposes various organic substances (odorous components) actually present inside and outside the vehicle, so that the rate at which the organic substances accumulate in the adsorbent can be suppressed and the photocatalyst is once adsorbed by the adsorbent. Organic matter can be oxidized and decomposed. Therefore, the photocatalyst filter 30 can be used stably without replacement for a long time.

[0024] Even if NOx or the like is oxidized or decomposed by the photocatalyst, if the NOX or the like is continuously adsorbed, the photocatalyst filter 3
0 removal performance is reduced. For this reason, in the automotive air purification device 10 of the first embodiment, the surface temperature of the photocatalytic filter 30 is increased by the halogen light from the halogen lamp 57 by stopping the air supply or performing the intermittent air supply, so that the air is adsorbed. the material was regenerated by elimination, addition, by accelerating the reaction rate of the photocatalyst, NO _X or oxidation and decomposition by the photocatalyst of the other persistent gas is further promoted, NOX adsorbed in the photocatalyst filter 30 The odor components such as are desorbed. At the same time, the adsorption filter 34
Is heated by the heating wire 46 to desorb NOx from the adsorbent filter 34 and to prevent the adsorbed filter from adsorbing the regenerated NOx desorbed from the photocatalytic filter. During this detachment operation, the damper 22 is opened,
NOx, HNO3, etc. separated from the activated carbon
To the air cleaner 72 and burned in the combustion chamber of the engine 70, or reduced to nitrogen by the three-way catalyst 74 to make it harmless and then discharged outside the vehicle.

Next, the operation of the automotive air purification device 10 according to the first embodiment of the present invention will be described with reference to the flowcharts of FIGS. When the driver turns on the start switch (not shown) in the control device 54 of the automotive air purification device 10 (Yes in S12)
s) The ultraviolet lamp 58 is turned on to emit ultraviolet light to the photocatalyst filter 30, thereby increasing the activity of the photocatalyst filter 30 (S14). And, by the downstream exhaust gas sensor 66,
Whether the capacity of the photocatalyst filter 30 has been reduced or not is determined by comparing the detected NOX concentration with a predetermined value X2 (S16). Here, when the performance of the photocatalyst filter 30 has not decreased (No in S16), the odor concentration detected by the downstream odor sensor 68 through the processing of step 32 is used to determine whether the performance of the adsorption filter 34 has decreased. Is compared with a predetermined value Y2 (S
34). Here, when the capacity of the adsorption filter 34 has not decreased (No in S34), the operation of purifying the air in the vehicle is started through the processing of step 36.

First, the damper 22 is operated to open the blow-out pipe 16 for sending purified air into the vehicle (S38). In this embodiment, the purification method is different depending on whether the air contains a large amount of exhaust gas components or a large amount of odorous components such as cigarettes. For this reason, first, it is determined whether the exhaust gas (NOX) measured by the upstream exhaust gas sensor 62 is higher than a preset concentration X1 (FIG. 4).
S72). Here, when the exhaust gas (NOX) is higher than the concentration X1 set in advance (S72: Y
es), a relatively weak output is given to the halogen lamp (heating lamp) 57 (S75), and the photocatalyst filter 30 and the oxidation catalyst filter 32 are heated to about 80 ° C. to increase the oxidation activity of both filters. Efficiently oxidize and decompose exhaust gas components. Then, the DC motor 40 is continuously rotated (S80), and the supply of air to the photocatalyst filter 30 and the oxidation catalyst filter 32 is started. This allows
The air taken in from the vehicle is pressure-fed and passed through the photocatalyst filter 30 to oxidize NO to NOx by the photocatalyst as described above, and is disposed at a position not heated by the activated carbon carried on the photocatalyst and the halogen lamp 57 on the downstream side. NOX is adsorbed on the adsorption filter 34,
The oxidation catalyst filter 32 converts CO in the air into harmless CO.
It is oxidized to 2 and then introduced into the car. This purifying operation is continued until the start switch is turned off (Yes in S82).
s).

On the other hand, the exhaust gas (NOX) measured by the upstream exhaust gas sensor 62 is supplied to a predetermined concentration X
If it is smaller than 1 (No in S72), the effect of increasing the activity of the photocatalyst filter 30 and the oxidation catalyst filter 32 by heating is small, so that the halogen lamp (heating lamp) 57 is turned off (S74). Then, the odor measured by the upstream odor sensor 64 is adjusted to a predetermined concentration Y1.
It is determined whether it is greater than (S76). Here, when the smell of tobacco or the like is higher than the preset density Y1 (Yes in S76), the DC motor 40 is continuously rotated to process a large amount of air (S80). If it is smaller than (No in S76),
The power consumption is suppressed by intermittently rotating the DC motor 40 (S78). When the start switch is turned off (Yes in S82), the motor is stopped and the lamp is turned off (S84), and the process ends.

Here, when the performance of the photocatalyst filter 30 is reduced by the purifying process, step 16 shown in FIG.
The determination as to whether or not the NOX concentration processed by the photocatalyst filter 30 is greater than the predetermined value X2 is Yes, the process proceeds to step 18, and the operation of desorbing the object to be adsorbed from the photocatalyst filter 30 is started. First, a relatively high output is given to the halogen lamp (heating lamp) 57 (S1).
8) The photocatalyst filter 30 and the oxidation catalyst filter 32 are heated to about 100 ° C. to increase the oxidation activity of both filters, so that the adsorbed exhaust gas components are efficiently desorbed. Then, the damper 22 is opened on the side where the exhaust pipe 18 communicating with the air cleaner 72 of the engine 70 is opened so as to send the detached exhaust gas to the engine 70 side (S2).
0). Next, a heating wire built in the adsorption filter 34 is energized to heat the adsorption filter 34 (S22), so that NOx and the like adsorbed by the adsorption filter 34 are desorbed and arranged upstream. Components such as NOx being regenerated desorbed from the photocatalytic filter 30 side are prevented from being adsorbed. Next, the temperature sensor 56 determines whether the surface temperature of the photocatalytic filter 30 is equal to or higher than a predetermined value (for example, 100 ° C.) (S24). Here, since the air is being pumped by the DC motor 40 and the photocatalytic filter 30 has been cooled, the determination in step 24 is No, the process proceeds to step 26, and the DC motor 40 is stopped (S2).
8).

Due to the decrease in the amount of air blow, the photocatalytic filter 30
Temperature rises to 100 ° C., the adsorbed substances are desorbed, and the activity of the photocatalyst increases. With this photocatalyst, NOx and the like adsorbed on the activated carbon are oxidized and decomposed and desorbed. Here, when the temperature of the photocatalyst filter 30 rises to 100 ° C., the determination in step 24 as to whether the temperature is equal to or higher than the predetermined temperature becomes No, and by rotating the DC motor 40 (S26), the temperature of the photocatalyst filter 30 becomes 100 ° C or lower. That is, steps 24 and 2
By the processes in steps 6 and 28, the DC motor 40 is operated intermittently, the photocatalyst filter 30 is kept at 100 ° C., and the desorption of the adsorbed substance is continued. NOx, HNO3 and the like separated from the photocatalyst filter 30 and the adsorption filter 34 are pressure-fed to the air cleaner 72 of the engine 70 as described above, and are burned in the combustion chamber of the engine 70 or converted to nitrogen by the three-way catalyst 74. After being reduced and rendered harmless, it is released outside the vehicle.

When the desorption is completed and the adsorbing force of the photocatalytic filter 30 recovers (S16: Yes), the process proceeds to step 32, where the halogen lamp (heating lamp) 57 is set to a relatively low output. After switching (S3
2) It is determined by the downstream odor sensor 68 whether or not the adsorption capacity of the adsorption filter 34 has decreased (S34). Here, when the performance of the adsorption filter 34 decreases (Yes in S34), the halogen lamp (heating lamp) 57 is switched to a relatively low output in the same manner as in the above-described regeneration of the photocatalytic filter 30, The adsorption filter 34 is regenerated. When the regeneration of the adsorption filter 34 is completed (No in S34), the energization of the heating wire 46 of the adsorption filter 34 is stopped (S36), and the air purification process is restarted.

Next, an air purifying apparatus according to a modification of the first embodiment will be described with reference to FIGS. FIG. 5 shows a configuration of an air purification device 110 according to a modification of the first embodiment. In the configuration described above with reference to FIG. 1, the photocatalyst filter 30 and the oxidation catalyst filter 32 were heated by the halogen lamp 57, and the adsorption filter 34 was heated by the heating wire 46. On the other hand, the modification shown in FIG. 5 employs a configuration in which the photocatalyst filter 30 and the oxidation catalyst filter 32 are heated by the heating wire 46 and the adsorption filter 34 is heated by the incandescent lamp 55.

FIG. 6 shows the configuration of an air purification device 210 according to another modification of the first embodiment. In the configuration described above with reference to FIG. 1, the photocatalyst filter 30 and the oxidation catalyst filter 32 are configured as separate filters.
In this modification, a photocatalyst is supported on the surface of one catalyst filter 35 on the side of the ultraviolet lamp 58A, and a noble metal oxide of CO is supported on the back surface. Further, in another modification shown in FIG. 6, the photocatalyst filter 30 and the oxidation catalyst filter 32 are heated by a pair of ultraviolet lamps 58A and 58B,
A configuration in which the suction filter 34 is heated by the incandescent lamp 55 is employed. That is, the ultraviolet lamps 58A and 58B
When oxidation and adsorption are performed by the photocatalyst filter 30, only one of the ultraviolet lamps 58A is turned on to activate the photocatalyst filter 30 with the ultraviolet light. By turning on 58B, the photocatalyst filter 30 can be heated. The catalyst filter 35
It is also preferable to support a photocatalyst and a CO oxidation catalyst on both surfaces of the catalyst, and further, a mixture obtained by kneading the photocatalyst and activated carbon powder into a honeycomb shape and using a CO oxide noble metal such as platinum supported thereon is used. Is also possible.

Next, a second embodiment of the present invention will be described with reference to FIG. 2B and FIGS. FIG. 7 shows a vehicle air purification device 310 according to the second embodiment.
Is shown. FIG. 2B shows a vehicle mounting position of the vehicle air purification device 310. FIG. 2 (B)
As shown in the figure, the air purification device 310 is disposed in the trunk room 202, the exhaust pipe 18 extends outside the vehicle, and the intake pipe 12 for taking in air and the blow-out pipe 16 for discharging purified air are led out of the vehicle. ing. The opening 18a of the exhaust pipe 18 is disposed at a position behind the rear glass 206 where a high negative pressure is generated.

In the first embodiment described above with reference to FIG. 1, the DC motor 40 is operated intermittently. However, in the second embodiment, the speed is controlled by the motor controller 54 so that a required amount of air can be fed. Is configured. Further, in the first embodiment, the halogen lamp 57 irradiates the halogen light to the photocatalyst filter 30 and the oxidation catalyst filter 32, but in the second embodiment, the output is 10 W and 1
An incandescent lamp 55 that can be switched by the lamp controller 51 to 00 W is used. In addition, about the member similar to 1st Embodiment, the same referential mark is used and description is abbreviate | omitted.

As shown in FIG.
Are an exhaust pipe 16 for blowing air into the vehicle, an exhaust pipe 18 for discharging exhaust gas to the outside of the vehicle, a first damper 21 for switching between the exhaust pipe 16 and the exhaust pipe 18, and an intake pipe for taking air from inside the vehicle. 12 and a second damper 22 for opening and closing the intake pipe. The vehicle air purification device 310 is controlled by the control device 54.

If NOx or the like is continuously adsorbed, the adsorbing filter 3
4 and the photocatalytic filter 30 have reduced adsorption performance. Therefore, in the air purification device 310 of the second embodiment, the surface temperature of the photocatalyst filter 30 is increased by increasing the light from the incandescent lamp 55 during regeneration, and the activity of the photocatalyst is increased. Further promoted, the photocatalyst and activated carbon of the photocatalyst filter 30 and the adsorption filter 3
The odor components such as NOX adsorbed on No. 4 are desorbed. At the time of the desorption operation, the intake pipe 12 is closed by the second damper 22 and the blow-off pipe 16 is closed by the first damper 21, so that the air purification device 310 is airtight, and the exhaust gas to which the negative pressure is applied. The air is exhausted to the outside of the vehicle through the pipe 18 to reduce the pressure, so that the photocatalytic filter 3
NOX, HNO3 from activated carbon and adsorption filter 34
Promotes the separation of

Next, the operation of the air purification device 310 according to the second embodiment of the present invention will be described with reference to the flowcharts of FIGS. First, the control device 54
It is determined whether a start switch (not shown) provided on the instrument panel on the driver's seat side has been operated (S112). here,
When the start switch is operated (S112: Yes
s) First, after turning on the ultraviolet lamp 58 (S11)
4) Whether the photocatalytic filter 30 needs to be regenerated (S11)
6) Or, it is determined whether the regeneration of the adsorption filter 34 is necessary (S118). That is, similarly to the first embodiment, the output from the downstream exhaust gas sensor 66 and the downstream odor sensor 68 deteriorates the adsorption performance of the photocatalytic filter 30 and the adsorption filter 34 and determines whether regeneration is necessary. Here, the case where the air purification can be started without the need for regeneration will be described first (No in S116, No in S118).

When purifying the air, the first damper 2
1 to close the exhaust pipe 18 and open the blowing pipe 16 (S162). Then, by operating the second damper 22,
The intake pipe 12 is opened (S164). Thereafter, the motor 40 is rotated at a high speed (S172 shown in FIG. 9). In the second embodiment, the purification method is different depending on whether the air contains a large amount of exhaust gas components or a large amount of odor components. Therefore, first, it is determined whether the exhaust gas (NOX) measured by the upstream exhaust gas sensor 62 is higher than a preset concentration X1 (S174). Here, when the exhaust gas (NOX) is higher than the preset concentration X1 (S174: Yes), the upstream odor sensor 6
It is determined whether the odor measured in Step 4 is higher than the preset density Y1 (S176). Here, when the smell of tobacco or the like is lower than the preset density Y1 (No in S178), the process proceeds to step 182, where a relatively low output is given to the incandescent lamp (heating lamp) 55 (S1).
82), photocatalyst filter 30 and oxidation catalyst filter 32
Is heated to about 80 ° C. to increase the oxidation activity of both filters, thereby efficiently oxidizing and decomposing exhaust gas components. As a result, the air taken in from the vehicle is pressure-fed and passed through the photocatalyst filter 30 to oxidize NO to NOx by the photocatalyst as described above, and adsorb NOX to the activated carbon carrying the photocatalyst and the downstream adsorption filter 34, Further, the CO in the air is oxidized to harmless CO2 by the oxidation catalyst filter 32 before being introduced into the vehicle. This purifying operation is continued until the start switch is turned off (S18).
4 is Yes).

On the other hand, the exhaust gas (NOX) measured by the upstream exhaust gas sensor 62 is set to a predetermined concentration X
When the value is smaller than 1 (No in S174), the effect of increasing the activity of the photocatalyst filter 30 and the oxidation catalyst filter 32 by heating is small, so that the incandescent lamp (heating lamp) 55 is used.
Is turned off (S180).

It should be noted that the determination in step 176 as to whether the odor concentration is greater than a preset value Y1 is made.
In the case of es, that is, when the amount of the exhaust gas component is large and the amount of the odor component is large, the process proceeds to step 178, where the odor concentration and the exhaust gas concentration are relatively larger than the set values X1 and Y1. Judge. Here, when the exhaust gas component is larger (Yes in S178), the process proceeds to step 182, and the processing for mainly oxidizing the exhaust gas is performed as described above. On the other hand, when the odor is larger (No in S178), the process proceeds to step 180, and the process for mainly absorbing the odor is started as described above.

Here, when the NOx adsorbing performance of the photocatalytic filter 30 is deteriorated and a relatively high concentration of NOx is detected by the downstream exhaust gas sensor 66 (S116 shown in FIG.
es) Or, if the adsorption performance of the adsorption filter 34 is deteriorated and the downstream odor sensor 68 detects an odor having a relatively high concentration (Yes in S118), the process proceeds to step 120, and the regeneration operation is started. Here, first, at step 120, it is determined whether the vehicle speed exceeds a first set value (for example, 40 km). If the vehicle speed has exceeded the first set value (Yes in S120), it is determined whether the vehicle speed has exceeded the predetermined time (for example, 10 seconds) (S10).
124). That is, it is determined whether the negative pressure required for the regeneration operation is continuously generated. Here, when the vehicle speed does not continuously exceed the set value (No in S120 or S1
24 is No), the process proceeds to step 162, and the above-described air purification is continued without performing the regeneration of the filter.

On the other hand, when the vehicle speed continuously exceeds the set value (S120: Yes, S124: Yes), the control device 54 operates the second damper 22 to operate the intake pipe 12
Is closed (S126), the first damper 21 is operated, and
The exhaust pipe 18 is opened and the blow-out pipe 16 is closed (S1).
28). That is, a high negative pressure is generated inside the air purification device 310 by preventing air from flowing from the intake pipe 12 and the discharge pipe 16. Then, the photocatalytic filter 30 is irradiated with relatively strong light (100 W) from the incandescent lamp 55 to heat the photocatalytic filter 30 (S138). At this time, the photocatalytic filter 3 is detected by the temperature sensor 56.
The surface temperature of 0 is measured, and when the surface temperature exceeds a predetermined value (for example, 100 ° C.), the surface temperature is maintained at the predetermined value by reducing the intensity of the light to be applied. Further, the heating wire built in the adsorption filter 34 is energized to make the adsorption filter 3
4 is heated (S140).

In the second embodiment, the substance to be adsorbed such as NOx is desorbed from the photocatalyst filter 30 and the adsorption filter 34 by heating under reduced pressure, and is discharged outside the vehicle through the exhaust pipe 18. At this time, it is determined whether the vehicle speed is higher than a third set value (a value lower than the first set value, for example, 30 km) (S148), and is determined to be higher than the third set value and generated according to the traveling speed. If the inside of the air purification device 310 can be sufficiently reduced in pressure only by the negative pressure (Yes in S148), the energy is saved by stopping the turbo fan 42 (S150). On the other hand, when the vehicle speed is not higher than the third set value (S148: No), the inside of the air purification device 310 is required by rotating the turbo fan 42 in addition to the low negative pressure generated during low-speed running. Reduce to atmospheric pressure.

Thereafter, it is determined whether or not the regeneration has been performed for the time set as the regeneration time (S152), and upon completion of the regeneration, the flow shifts to step 160 to resume the air purification. On the other hand, until the reproduction is completed (No in S152),
The vehicle speed is lower than a second set value (for example, 35
km) (S156). here,
When the vehicle speed is equal to or higher than the second set value (S156 is N
o), returning to step 140 and continuing the reproduction process. On the other hand,
When the vehicle speed is lower than the second set value (S156
s) Further, it is determined whether the state lower than the second set value continues for a predetermined time (for example, 30 seconds) (S158). Here, unless the low state continues for a predetermined time (S158 is N
o), returning to step 140 and continuing the reproduction process. On the other hand,
If the low state continues for a predetermined time, the routine proceeds to step 160, where the regeneration operation is interrupted and the air purification is restarted. Here, even if the regeneration operation is interrupted and air purification is resumed, step 116 or step 118 is performed during the purification process.
When the vehicle speed continues to exceed the first set value (Yes in S120 and S124), the reproduction operation is restarted (S128 to S15).
8).

The air purification device 310 of the second embodiment
Since the photocatalyst filter 30 and the adsorption filter 34 are regenerated using the negative pressure generated in the vehicle, the removal rate at the time of the regeneration can be increased. At this time, since the intake pipe 12 and the blowing pipe 16 are closed, the pressure inside the air purification device 310 can be reduced to a low pressure, and the removal rate can be increased. In particular, since this pressure reduction is performed by using the negative pressure generated in the vehicle, there is an advantage that energy is not consumed as compared with the case where the pressure is reduced by using a motor or the like. In the second embodiment, the exhaust gas is directly discharged to the outside of the vehicle. However, the exhaust gas can be discharged to the outside of the vehicle through the trunk room by extending the exhaust pipe to the trunk room where the negative pressure is generated. is there.

According to the first and second embodiments, the deterioration of the photocatalytic filter and the adsorption filter are determined separately, and the regeneration is performed so as to be optimal for each. it can.

Next, a third embodiment of the present invention will be described with reference to FIGS. FIG.
4 shows a configuration of an air purification device 410 according to the embodiment. In the first and second embodiments described above, the air purification method of the present invention is applied to an air purification device for a vehicle.
In the embodiment, the air purification method of the present invention is applied to an air purification device disposed indoors. In the configuration of the third embodiment, together with the photocatalyst filter 30, the adsorption filter 34, and the like,
The control device 54 and the lamp control circuit 50 are integrated into the housing 302. Further, in the third embodiment, an exhaust pipe for exhausting gas desorbed at the time of regeneration to the outside extends to the outside of the room.

Here, the operation of the air purification device 410 according to the third embodiment will be described with reference to the flowchart of FIG. The control device 54 of the air purification device 310 includes:
When the start switch (not shown) is turned on (S312: Yes), the ultraviolet lamp 58 is turned on, and ultraviolet rays are emitted to the photocatalyst filter 30 to increase the activity of the photocatalyst (S31).
4) Then, the DC motor 40 is rotated (S316), and the supply of air to the photocatalyst filter 30 is started. Then, it is determined whether the adsorption performance of the adsorption filter 34 has deteriorated based on the output from the downstream odor sensor 68 (S318). Here, when a high concentration odor is detected (S318: Ye
s), the filter replacement lamp 69 shown in FIG. 10 is turned on (S320).

Next, at step 322, the exhaust gas (NOX) measured by the upstream exhaust gas sensor 62 is
It is determined whether the density is higher than the preset density X1 (S
322). Here, when the exhaust gas (NOX) is higher than the concentration X1 set in advance (S322: Ye
s) By energizing the heating wire 46, the catalyst filter 30 and the oxidation catalyst filter 32 are heated to about 80 ° C., the oxidation activity of both filters is increased, and the exhaust gas components are efficiently oxidized and decomposed. This purifying operation is continued until the start switch is turned off (Yes in S328).

On the other hand, when the exhaust gas (NOX) measured by the upstream exhaust gas sensor 62 is
When it is smaller than 1 (No in S322), the heating wire 4
6 is stopped (S326).

Next, the operation of the air purifying apparatus according to the modification of the third embodiment will be described with reference to the flowchart of FIG. In the embodiment described with reference to FIG. 11, the odor concentration is detected by the odor sensors 62 and 68, and the adsorption filter and the like are automatically regenerated. In this modification, a mode setting switch is provided. The regeneration of the photocatalytic filter 32 and the adsorption filter 34 is performed in accordance with the mode (heavy mode, light mode, pet mode, normal mode) set in this switch.

Here, the heavy mode is set when smoking frequently, the light mode is set when smoking is infrequent, but the pet mode is set in the room where the pet is. The normal mode is set in a room where there is no smoking and no pets.

The operation of this modification will be described with reference to the flowchart of FIG. First, it is determined whether the heavy mode is set to the mode setting switch (S352). Here, if the heavy mode is set (S352: Yes), the heavy mode flag is set (S354). Similarly, it is determined whether the write mode is set (S356). If the write mode is set, a write mode flag is set (S358). If the pet mode is set (Yes in S360), the pet mode flag is set (S354). If the normal mode is set (S364), a normal mode flag is set (S36).
8).

Subsequently, it is determined whether it is the photocatalytic regeneration time (S370). Here, when the heavy mode flag is set, the reproduction is performed once every two days (Y in S372).
es). If the heavy mode flag is set, the photocatalyst filter 32 is heated for 20 minutes to perform regeneration (S374).

On the other hand, if the write mode flag is set, reproduction is performed once every three days (S272: Yes
s). If the light mode flag is set, the photocatalyst filter 32 is heated and regenerated for 20 minutes (S374). If the pet mode flag is set, the reproduction is performed once every four days (S272).
Is Yes). In this case, the photocatalyst filter 32 is heated and regenerated for 10 minutes (S374). When the normal mode flag is set, the reproduction is performed once every six days (Yes in S272). At this time, the photocatalyst filter 32 is heated and regenerated for 10 minutes (S374).

Subsequently, it is determined whether it is the regeneration time of the adsorbent (S380). Here, if the heavy mode flag is set, reproduction is performed once a day (Y in S382).
es). If the heavy mode flag is set, the adsorption filter 34 is heated for 20 minutes to perform regeneration (S384).

On the other hand, when the write mode flag is set, reproduction is performed once every two days (S272: Yes
s). If the light mode flag is set, the suction filter 34 is heated and reproduced for 20 minutes (S384). If the pet mode flag is set, the reproduction is performed once every two days (Yes in S272). In this case, the adsorption filter 34 is used for 10 minutes.
Is reproduced by heating (S384). When the normal mode flag is set, reproduction is performed once every four days (S2
72 is Yes). In this case, the suction filter 3 is used for 10 minutes.
4 is heated and regenerated (S384).

In the third embodiment, the adsorbed filter 34 is regenerated and the desorbed gas is discharged to the outside of the room for use. Even when the fuel cell 34 is deteriorated, it is possible to omit the exhaust pipe by replacing it without heating.

In the first to third embodiments, the incandescent lamp 55 or the halogen lamp 57 and the heating wire 46 are used.
Although the photocatalyst filter 30 and the adsorption filter 34 were heated in the above, the heating can be performed by various methods. For example, it is also possible to circulate the cooling water of the engine through the filter 30 and heat it, and further heat it by irradiating microwaves using a magnetron or the like. Also, in the above embodiment, the photocatalytic filter 30 is set to 80 ° C.
Although it is heated to the extent, it is also preferable that the amount of light irradiation or the amount of air blow is adjusted according to the outside air temperature so that the efficiency of the photocatalyst is adjusted to be the highest temperature.

In the first to third embodiments, a black light is used as the ultraviolet lamp, but various lamps can be used as long as the photocatalyst can be excited. Furthermore, although TiO2 was used as the photocatalyst, various materials can be used as long as the odor components can be oxidized and decomposed. For example,
Ti, Cu, Zn, La, Mo, V, Sr, Ba, C
It can be composed of at least one selected from the group consisting of oxides of e, Sn, Fe, W, Mg, or Al, and noble metals. Further, in the above embodiment, the NO value was measured as the exhaust gas concentration, but it is also possible to measure the CO concentration instead.

[0061]

As described above, the first, third, and fourth aspects of the present invention are described.
According to the air purification method and apparatus, when a gas concentration higher than a predetermined value is detected, the oxidation catalyst is heated to increase the activity, thereby efficiently purifying a gas having a relatively high concentration. On the other hand, when a gas concentration lower than the predetermined value is detected,
By stopping the heating and keeping the room temperature, the air is efficiently purified by the adsorbent. Therefore, the most appropriate purification can be performed in accordance with the components in the processing air.

According to the second aspect of the present invention, the oxidation catalyst is saturated,
When a gas concentration higher than a predetermined value is detected, the oxidation catalyst is regenerated by heating. At this time, the gas desorbed from the oxidation catalyst goes to the adsorbent on the downstream side, but by heating the adsorbent, the gas is prevented from being adsorbed by the adsorbent. On the other hand, when the adsorbent is saturated and a gas concentration higher than a predetermined value is detected, the adsorbent is heated and regenerated. For this reason, in the air purification device that purifies air using the oxidation catalyst and the adsorbent, the oxidation catalyst and the adsorbent can be efficiently regenerated.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a vehicle air purification device according to a first embodiment of the present invention.

FIG. 2A is an explanatory view showing a mounting position of an automotive air purification device according to a first embodiment;
(B) is an explanatory view showing a mounting position of the automotive air purification device in the second embodiment.

FIG. 3 is a flowchart showing a regeneration operation of the automotive air purification device of the first embodiment.

FIG. 4 is a flowchart showing a purification operation of the vehicle air purification device of the first embodiment.

FIG. 5 is a configuration diagram of an automotive air purification device according to a modification of the first embodiment of the present invention.

FIG. 6 is a configuration diagram of an air purification device for an automobile according to another modification of the first embodiment of the present invention.

FIG. 7 is a configuration diagram of a vehicle air purification device according to a second embodiment of the present invention.

FIG. 8 is a flowchart showing a regeneration operation of the automotive air purification device of the second embodiment.

FIG. 9 is a flowchart showing a purification operation of the automotive air purification device of the second embodiment.

FIG. 10 is a configuration diagram of an air purification device according to a third embodiment of the present invention.

FIG. 11 is a flowchart showing the operation of the air purification device of the third embodiment.

FIG. 12 is a flowchart showing an operation of an air purification device according to a modification of the third embodiment.

[Explanation of symbols]

 Reference Signs List 10 Air purification device for automobile 30 Photocatalyst filter 32 Oxidation catalyst filter 34 Adsorption filter 42 Turbo fan 55 Incandescent lamp 57 Halogen lamp 58 Ultraviolet lamp 70 Engine 74 Three-way catalyst

──────────────────────────────────────────────────の Continuation of the front page (51) Int.Cl. ⁶ Identification symbol FI B01J 20/20 B01D 53/36 A 35/02 J (72) Inventor Masako Sakai 2-9-112 Sotokanda, Chiyoda-ku, Tokyo Equos Research Co., Ltd.

Claims (4)

[Claims] 1. An oxidation catalyst, an adsorbent disposed downstream of the oxidation catalyst, an oxidation catalyst heating means for heating the oxidation catalyst, and an oxidation catalyst for controlling the heating intensity of the oxidation catalyst heating means A heating intensity change commanding means for sending a command to change the heating intensity by the oxidation catalyst heating control means to the oxidation catalyst heating control means, An air purification apparatus, wherein a control means receives a command from the heating intensity change command means, and regenerates the oxidation catalyst by strengthening the heating intensity of the oxidation catalyst heating means. 2. The air purification device according to claim 1, wherein said oxidation catalyst heating means includes an ultraviolet irradiation means. 3. The air purification device according to claim 1, wherein the oxidation catalyst contains a photocatalyst. 4. The air purifying apparatus according to claim 1, wherein the adsorbent contains activated carbon.