JPH09175165A - Method and device of purifying air for automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a device purifying air for an automobile which prevents releasing to outside a car a harmful component removed from the air, while the outside air, having removed a harmful component therein, can be taken in the car in the case of introducing the outside air in the car. SOLUTION: The outside air is introduced from an outside air introducing hole 12a, after adsorbing NOx in an activated carbon fiber 34 of first/second columns 30A, 30B, to be introduced into a car from a blow port 13a. This activated carbon fiber 34, by heating it with NOx separated, is repeatedly used. Here, separated NOx by heating is fed to an engine 80 and catalytic converter rhodium 81, wherein NOx is reduced to N2 and discharged outside the car.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automobile air purification method and device for purifying harmful gases in the air sent into a vehicle.

[0002]

2. Description of the Related Art Conventionally, air purifiers for automobiles have generally used an electric dust collecting system in which air inside a vehicle is circulated by a fan and dirt is removed by a filter. This uses a filter material that is prone to being electrically charged with static electricity to adsorb foreign matter such as dust. In addition, an ion type air purifier equipped with a corona discharge mechanism in a portion corresponding to a filter is incorporated in a vehicle air control unit.

An ion type air purifier is a prefilter,
It consists of an ionizer and a collector unit. Dirty air sent from the outside or inside of the vehicle by the blower fan is first cleaned of large dust by a pre-filter. The dust in the air is charged by an ionizer that performs high-pressure corona discharge, and the charged dust is collected by a collector to purify the air.

[0004]

The above-described vehicle-mounted air purifier has the ability to remove particles such as cigarette smoke or dust and soot floating in the air, but other vehicles. NO _X discharged from, could not remove toxic gases such as CO. For this reason, while traveling on a congested road or the like or a road with a large traffic volume, air containing harmful gas outside the vehicle has been directly introduced into the vehicle.

Therefore, when traveling on a congested road or the like having a high NO _x and CO concentration, the blower of the vehicle is switched to the internal air circulation to prevent the harmful gas from entering the vehicle. However, since outside air enters through various gaps in the vehicle,
When traveling in an area where the NO _X and CO concentrations are high, the invasion of NO _X and CO could not be prevented even by circulating the inside air.

On the other hand, when the inside air is circulated in order to suppress the amount of NO _x and CO entering the vehicle, the CO discharged by the passenger is discharged.
₂ is not discharged to the outside of the vehicle, there is a problem that increases the car CO ₂ concentration.

In order to meet such a problem, the present applicant has
Using an adsorbent to adsorb the harmful gases such as NO _X, then the harmful gas adsorbed was separated from the adsorbent by heating, by enabling reuse and exchange sorbent over time I devised a method to purify the air without.

However, in the above method, a new problem arises as to how to treat the harmful gas separated from the adsorbent.

The present invention has been made in order to solve the above-mentioned problems, and an object of the present invention is to introduce air from which harmful components have been removed into a vehicle and to remove harmful substances removed from the air. An object of the present invention is to provide a method and an apparatus for purifying air for an automobile, which does not release components outside the vehicle.

Further, according to the present invention, when the outside air is introduced into the vehicle, the harmful components in the outside air can be removed and taken into the vehicle, and the harmful components removed from the air are not released to the outside of the vehicle. It is an object of the present invention to provide a purification method and device.

[0011]

In order to achieve the above object, in the method for purifying air for a vehicle according to claim 1, air containing harmful gas is brought into contact with an adsorbing member to adsorb the harmful gas and then introduced into the vehicle to physically. Of the harmful gas from the adsorbent member by a physical or chemical method, sends the harmful gas separated from the adsorbent member to an engine equipped with an exhaust gas purification device, The technical feature is that the harmful gas is adsorbed again by bringing it into contact with air containing gas.

Further, in order to achieve the above-mentioned object, claim 2
In the air purification method for automobiles, after the air containing harmful gas outside the vehicle is brought into contact with the adsorption member to adsorb the harmful gas, it is introduced into the vehicle and the harmful gas is separated from the adsorption member by a physical or chemical method. Then, the harmful gas separated from the adsorption member is sent to an engine equipped with an exhaust gas purification device, and the adsorption member separated from the harmful gas is brought into contact with air containing the harmful gas to adsorb the harmful gas again. Is a technical feature.

In order to achieve the above object, in the automobile air purifying apparatus according to the third aspect of the present invention, NO _x mainly composed of activated carbon is used.
Adsorbing member, a blowing means for feeding the air outside the vehicle containing NO _X to the adsorbing member, and introducing the air adsorbing NO _X into the vehicle, and the adsorbing operation for adsorbing NO _X by the blowing means. Heating means for heating the member to remove the NO _x adsorbed by the adsorbing member, and exhaust feeding means for sending the NO _x detached from the adsorbing member by the heating means to an engine equipped with an exhaust purification device. The technical feature is that it consists of.

Further, in order to achieve the above-mentioned object, claim 4
In the automobile air purification device, the container for accommodating the NO _X adsorbing member mainly composed of activated carbon, the precious metal catalyst having the redox ability, and the outside air containing NO _X and CO are sent to the container, A blower means for adsorbing NO _x on the activated carbon and introducing air in which CO is oxidized to CO ₂ by a precious metal catalyst into the vehicle, and the blower means N
Heating means for heating the adsorption member of the container in which the adsorption operation of O _X has been performed and for separating the NO _X from the adsorption member;
The technical feature is that it comprises NO _x separated from the adsorption member by the heating means, and an exhaust feed means for sending the NO _x to an engine equipped with an exhaust purification device.

In order to achieve the above object, an automobile air purifying apparatus according to a fifth aspect is characterized in that, in the third or fourth aspect, the activated carbon is an activated carbon fiber.

In order to achieve the above object, in the air purifying apparatus for an automobile according to claim 6, according to claim 3 or 4, it is technical that the air blowing means and the exhaust air feeding means are driven by a single motor. Characterize.

[0017] To achieve the above objects, the automotive air purification device according to claim 7, in claim 3 or 4, wherein the exhaust feeding means, technical features to send NO _X to the engine by the negative pressure of the engine And

[0018]

According to the first aspect of the invention, air is sent to the adsorbing member made of activated carbon or the like to adsorb the harmful gas. Therefore, the air from which the harmful gas has been separated can be sent into the vehicle. Here, after the harmful gas is adsorbed to the adsorbing member, the harmful gas is released by a physical or chemical method such as heating. Can be adsorbed. Further, since the separated harmful gas is sent to the engine equipped with the exhaust gas purification device, the harmful gas can be burned by the engine or purified by the exhaust gas purification device, and the harmful gas is not discharged to the outside of the vehicle. .

Further, according to the second aspect of the present invention, since the air outside the vehicle is sent to the adsorbing member made of activated carbon or the like to adsorb the harmful gas, the air from which the harmful gas is separated can be sent into the vehicle. For this reason, even when the vehicle is traveling in an area where the level of harmful gas is high, the outside air can be introduced and the CO ₂ exhaled by the passengers inside the vehicle can be released to the outside of the vehicle.
₂ levels can be reduced. Further, since the harmful gas separated by the physical or chemical method is sent to the engine equipped with the exhaust gas purification device, the harmful gas can be burned by the engine or purified by the exhaust gas purification device. Is never discharged outside the vehicle.

Further, in the invention of claim 3, the blower means comprises:
For monkey adsorbs NO _X feeding air outside the vehicle to mainly of the suction member from the activated carbon, the air that has left the NO _X can be sent to the vehicle. Therefore, even when the vehicle is traveling in an area where the NO _X level is high, it is possible to introduce outside air and release the CO ₂ exhaled by passengers inside the vehicle to the outside of the vehicle.
The O ₂ level can be lowered. The heating means is, for detached from the suction member the NO _X by heating the adsorbing member, a completed suction member leaving the NO _X, the NO _X in contact with air can be re-adsorbed. Further, the exhaust gas feeding means sends the NO _x separated by heating to the engine equipped with the exhaust gas purification device, and burns the NO _x in the engine or purifies it with the exhaust gas purification device.
Never eject _{X out} of the car.

Further, in the invention of claim 4, the blower means comprises:
A vessel containing activated carbon and a noble metal catalyst feeding the outside air containing the NO _X and CO, the NO _X adsorbed in the activated carbon, since the CO is introduced into the vehicle after oxidation to CO ₂ in a noble metal catalyst, NO _X The air separated from CO and CO can be sent into the vehicle. Therefore, even when the vehicle is traveling in an area where the levels of NO _x and CO are high, the outside air can be introduced to discharge the CO ₂ exhaled by passengers inside the vehicle to the outside of the vehicle, thereby lowering the CO ₂ level in the vehicle. You can The heating means heats the adsorbing member, to disengage the NO _X from the suction member, the completed suction member leaving the NO _X, the NO _X in contact with air can be re-adsorbed.
Further, the exhaust gas feeding means sends the NO _X separated by heating to the engine equipped with the exhaust gas purification device, and burns the NO _X gas by the engine or purifies it by the exhaust gas purification device, so that the NO _X gas is discharged outside the vehicle. There is nothing to do.

According to the invention of claim 5, the activated carbon is made of activated carbon fiber, so that the pressure loss during air blowing is reduced. Moreover, a large amount of NO _x can be adsorbed by the activated carbon fiber having a small capacity.

Further, according to the invention of claim 6, the air blowing means and the exhaust feeding means are driven by a single motor, so that the air purifying device for an automobile can be constructed at a low cost.

[0024] In the present invention of claim 7, the exhaust feeding means, for feeding the NO _X to the engine by the negative pressure of the engine, it is possible to inexpensively constitute the automobile air purifier.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION 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. 2 (A), the automobile air purification device 10 is housed in the trunk behind the vehicle compartment of the vehicle, and the exhaust pipe 19 extends to the air cleaner 82 of the engine 80. Further, the intake pipe 18 extends from the air control unit 84 side. Further, the automobile air purification device 10 has an inside air intake hole 11a for taking in the air in the vehicle interior, an outside air intake hole 12a for taking in air from the outside of the vehicle, and a blown air for purifying the inside of the vehicle interior. The outlet 13a is provided.

As shown in FIG. 1, an air purifying apparatus 10 for an automobile has a ventilation pipe 14 for taking in air and discharging exhaust gas, a blower 40 for pumping air, and a first column 30A for purifying air. The second column 30B and the air outlet pipe 13 that guides the air purified by the first and second columns 30A and 30B to the outlet 13a in the vehicle compartment are mainly configured.

The ventilation pipe 14 includes an intake pipe 18 from the air control unit 84 side, an inside air intake pipe 11 for taking in the air in the vehicle compartment, an outside air intake pipe 12 for taking in air from the outside of the vehicle, and an engine 80. The exhaust pipe 19 extending to the air cleaner 82 is connected. A first damper 21 that closes the inside air intake pipe 11 is disposed between the ventilation pipe 14 and the inside air intake pipe 11.
A second damper 22 that closes the outside air intake pipe 12 is arranged between the ventilation pipe 14 and the outside air intake pipe 12. Further, a third damper 23 that closes the exhaust pipe 19 is provided between the ventilation pipe 14 and the exhaust pipe 19.
A humidity sensor 42 for detecting the humidity of the inhaled air is arranged in the ventilation pipe 14.

An evaporator 84a for dehumidification is arranged in the air control unit 84, and the evaporator 8 is
On the intake side of 4a, an inside air intake pipe 16 for taking in air inside the vehicle compartment and an outside air intake pipe 17 for taking in air from outside the vehicle are attached. Between the evaporator 84a and the inside air intake pipe 16, the inside air intake pipe 16 is
A seventh damper 27 for closing the outside air intake pipe 17 and an eighth damper 27 for closing the outside air intake pipe 17 between the seventh damper 27 and the outside air intake pipe 17.
A damper 28 is provided.

Air is supplied to the engine 80 via an air cleaner 82, and the air cleaner 82 is connected to the exhaust pipe 1 of the automobile air purification apparatus 10.
9 are connected. The engine 80 is controlled by an ECU (engine control unit) 90. EC
U90 detects the oxygen concentration in the exhaust gas by the oxygen sensor 86, controls the fuel injection device 83, and sets the air-fuel ratio to 1
The fuel is supplied to about 3.8 and the ignition timing to the plug 85 is adjusted to suppress the generation of NO _{X in} the combustion chamber, thereby oxidizing CO, HC, and NO _{X in} the three-way catalyst 81.・ CO, HC, N by performing reduction properly
The release of the O _X of the vehicle exterior is minimized.

The blower 40 for pumping the air in the ventilation pipe 14 is provided with the first and second columns 30 through the branch pipe 15.
It is connected to A and 30B. The branch pipe 15 is provided with a fourth damper 24 that distributes the pressure-fed air to either the first column 30A or the second column 30B. A fifth damper 25 that closes the first column 30A is provided between the first column 30A and the air outlet pipe 13.
Further, between the second column 30B and the air outlet pipe 13,
A sixth damper 26 that closes the second column 30B is provided. The air outlet pipe 13 has a first column 30A.
Alternatively, the NO _x sensor 44 for detecting the NO _x concentration in the air purified by the second column 30B is provided.

Here, the first and second columns 30A and 30B
The configuration will be described with reference to FIG. The first column 30A and the second column 30B shown in FIG.
It consists of a box-shaped container 38 of 0 × 200 mm. This box-shaped container 3
Silica gel 32 as a dehumidifying agent is filled with a thickness of 60 mm on the air introduction side of 8 as shown in FIG. 3 (A), and a heater wire 39 is passed through the silica gel 32 to heat the absorbed moisture. It is configured to be able to diverge. In this embodiment, silica gel is used as the hygroscopic agent, but various materials such as zeolite and activated alumina can be used as long as they can separate water by heating and reuse it.

At the center of the box-shaped container 38 shown in FIG.
Activated carbon fibers 34 for adsorbing O _X are arranged. This activated carbon fiber 34 has a length and width of 200 × 200 mm.
Then, it is folded into a pleat shape with a height of 100 mm and is housed in the box-shaped container 38 (see FIG. 3B). That is, the activated carbon fiber 34 (0.8
m ² ) is housed in a box-shaped container 38 of 200 × 200 mm in length and width to reduce the passage speed of air and reduce pressure loss. A heater wire 39 for heating is arranged on the activated carbon fiber 34 as shown in FIG. 3 (B). In addition,
As the heating method of the silica gel 32 and the activated carbon fiber 34, in addition to the above method, a dielectric heating method, an electric resistance heating method, a method of heating with hot air heated by engine exhaust heat, or the like can be applied. It is not limited.

As the activated carbon fiber 34, for example,
Fineguard (registered trademark) made of acrylic fiber provided by Toho Rayon Co., Ltd. can be used. This fine guard has a specific surface area of 500 to 1200 m ^2.
/ G, average pore diameter 20-40Å, fiber diameter 7-15μ
m, fiber tensile strength 20 to 50 kg / mm ² , N content 2-1
The FE-200 in which the fine guard is made into a felt shape is provided, which has characteristics of 0%, an external surface area of 0.2 to 0.7 m ² / g, and benzene equilibrium adsorption of 20 to 50%. (Basis weight 100 g / m ² ) is shown in Fig. 3 (B).
As described above with reference to FIG. This activated carbon fiber 34 adsorbs NO _X and also S
O _X, strongly adsorbs cigarette odors.

The activated carbon fiber 34 is heated by the heater wire 39 when NO _x is adsorbed and its performance deteriorates.
Repeatedly used by removing _X.

At the most downstream side of the box-shaped container 38 shown in FIG.
A Pd catalyst 36 is provided for oxidizing CO to CO ₂ . The Pd catalyst 36 is formed by supporting Pd on the activated carbon fiber 35 as shown in FIG. 3 (C). The activated carbon fiber 35 is folded into a pleat shape with a height of 40 mm and is housed in a box-shaped container 38 like the activated carbon fiber 34 for NO _x adsorption. That is, by accommodating the activated carbon fiber 35 having a large area, the passage speed of air is reduced and the pressure loss is reduced. It should be noted that the Pd catalyst 36, which is not deteriorated by use, is not provided with a heater wire for heating.

Here, the activated carbon fiber 3 shown in FIG.
The results of testing the NO _X adsorption performance of No. 4 will be described with reference to FIG. 12, the time of flow 10 liters / min as the flow rate of the gas, the concentration of NO _X and the inlet side and the outlet side of the activated carbon fiber 34 shows the results of measurement by the sensor. At the time of 0 seconds, 400 seconds, and 800 seconds, a sensor is arranged on the entrance side of the activated carbon fiber 34 (before NO _X removal),
When 200 seconds, 600 seconds, and 1000 seconds have passed, the sensor is moved to the exit side of the activated carbon fiber 34 (after NO _X removal). As is apparent from this test, 2 to activated carbon fiber 34 a NO _X of 2.7ppm is reduced to 0.2 ppm.

Next, the results of testing the NO adsorption performance of the activated carbon fiber 34 will be described. First, a description will be given state of the NO _X in the air prior to this description. NO is mainly emitted as NO _X from a gasoline engine or a diesel engine. Since this NO is not stable in the atmosphere, it gradually becomes NO ₂ with the passage of time.
Etc. to NO _X (here, X means more than 1 in particular). Therefore, on a congested road, the proportion of NO in NO _X is high, but the proportion of NO ₂ is low, but when measured at a position slightly away from the road, for example, the proportion of NO decreases and NO ₂ Is increasing. Here, since the outside air is introduced from a low position on the road, the air taken into the vehicle has a high proportion of NO, but a low proportion of NO ₂ . Therefore, when purifying NO _X in the air taken in from outside the vehicle, whether or not capable of adsorbing NO is a problem. Here, although activated carbon (including activated carbon fiber) is generally excellent in NO ₂ adsorption performance,
Was believed to have a poor adsorption capacity.

The present inventor came to the idea that the NO adsorption capacity of the activated carbon could be increased by lowering the humidity, and the relative humidity was lowered by the dehumidifying agent as shown in FIG. The NO adsorption capacity of the activated carbon fiber 34 shown in () was tested. FIG. 13 shows that when the relative humidity is maintained at about 3% and the gas flow rate is 10 liters / minute,
The results of measuring the NO concentrations on the inlet side and the outlet side of the activated carbon fiber 34 by the sensor are shown. 0 seconds, 500 seconds, 1
When 100 seconds have passed, the sensor is arranged on the entrance side (before NO removal) of the activated carbon fiber 34, and after 200 seconds or 700 seconds, the sensor is moved to the exit side (after NO removal) of the activated carbon fiber 34. ing. From this test, activated carbon fiber 34 is 5pp
It was found that NO of m 2 was reduced to 1 to 2 ppm, and the activated carbon fiber 34 could sufficiently adsorb NO by lowering the humidity.

In this experiment, activated carbon fiber was used and the relative humidity was set to 3%, but from the results of other experiments, when activated carbon was used, the absolute humidity was 2.1 [g / (kg-D
A)] (corresponding to about 10% relative humidity at 26 ° C)
It was found that NO can be adsorbed by keeping the amount below.

Next, the regeneration of the activated carbon fibers 34 by heating will be described with reference to FIG. In the figure, X indicates the adsorption performance of NO by the activated carbon fiber 34 before regeneration,
Y in the figure is NO after heating in a constant temperature bath at 100 ° C for 30 minutes
_X desorption performance but were separated in, Z is shows the adsorption performance but were elimination of heated and irradiated for 2 minutes with microwaves of a second embodiment to be described later NO _X.

Here, the values are shown when a gas of 3 l / min was passed through the activated carbon fiber 34 at a relative humidity of 10%. In the activated carbon fiber 34 before regeneration, as shown by the curve X, the NO concentration of 5 ppm can be reduced to only 3.7 ppm. On the other hand, in the activated carbon fiber 34 heated in the constant temperature bath, as shown by the curve Y, the NO concentration of 6 ppm is reduced to about 3 ppm.
In addition, the activated carbon fiber 34 heated by the microwave is
As indicated by Z in the figure, the adsorption performance is similar to the value indicated by the curve Y which was regenerated by heating in a constant temperature bath.

Next, CO is removed by the Pd catalyst 36 shown in FIG. 3 (C), that is, CO is oxidized to a harmless low concentration of C.
The result of the ability test for O ₂ will be described with reference to FIG. FIG. 15 shows the results of measuring the CO concentrations on the inlet side and the outlet side of the Pd catalyst 36 with a sensor when a gas flow rate of 10 liters / minute was flown. here,
Keep the temperature constant at 25 ° C and keep the relative humidity from 40% to 3%.
The experiment was conducted by gradually lowering it to 0%. The Pd catalyst used was one in which Pd was supported by γ-Al ₂ O ₃ . Here, when 0 seconds and 400 seconds have elapsed, a sensor is arranged on the inlet side of the Pd catalyst 36 (before CO removal), and 200 seconds and 60 seconds
When 0 second has elapsed, the sensor is moved to the exit side of the Pd catalyst 36 (after CO removal). From this test, the Pd catalyst 36
It has been found that the CO concentration of 25 ppm can be reduced to about 10 ppm at room temperature.

[0043] From the above test results, the first, second column 30A, 30B shown in FIG. 1, after adsorbing the moisture in the air on silica gel 32, adsorbs NO _X by passage through activated carbon fiber 34, Further, CO can be oxidized by the Pd catalyst 36 into CO ₂ . That is, NO _X and C
It becomes possible to introduce outside air containing O, remove NO _X and CO, and then introduce it into the vehicle. CO is CO
_Although it will be introduced into the vehicle as _2, the CO ₂ concentration in the vehicle that circulates the inside air is 5 in the general measurement result.
It reaches 000ppm, while CO is oxidized to CO ₂
Because the concentrations are of the order of several 10 ppm, car CO ₂
It does not increase the concentration.

When the NO _x and CO are continuously purified as described above, the silica gel 32 absorbs humidity to
In addition, the performance of the activated carbon fiber 34 deteriorates due to the adsorption of NO _X. Therefore, in the automobile air purification device 10 of the present embodiment, the silica gel 32 and the activated carbon fibers 34 of the first and second columns 30A and 30B are heated and regenerated by passing an electric current through the heater wire 39. During this regenerating operation, the third damper 23 is opened and the blower 40 is rotated in the reverse direction so that the NO _X separated from the activated carbon fiber 34 is pressure-fed to the air cleaner 82 of the engine 80. During the reproducing operation, the first damper 21, the second damper 22, the seventh damper 27, and the eighth damper 2 shown in FIG.
8 is closed to prevent the NO _X separated from the activated carbon fiber 34 from leaking inside and outside the vehicle.

NO _X separated from the activated carbon fiber 34
Are sucked into the combustion chamber of the engine 80 together with air. Here, the ECU 90 detects the oxygen concentration in the exhaust gas discharged from the combustion chamber by the oxygen sensor 86 and controls the fuel injection device 83 to set the air-fuel ratio to about 13.8, that is, the ideal air-fuel ratio By supplying fuel so that the fuel ratio becomes rich, delaying the ignition timing of the plug 85 to lower the temperature of the combustion chamber, and allowing the generation of CO and HC, the generation of NO _X in the combustion chamber is suppressed. Then, in the three-way catalyst 81, NO
The reduction of _X is performed by the following formula. 2NO + 2CO → N ₂ + 2CO ₂ 4NO + CH ₄ → CO ₂ + 2H ₂ O + 2N ₂ 2NO + 2H ₂ → N ₂ + 2H ₂ O

At the same time as this NO _X reduction, the three-way catalyst 81
Inside, oxidation of HC and CO is performed. Accordingly, to suppress CO as a harmful gas, HC, the release of the outside of the NO _X to a minimum. Thus, in this embodiment, the existing engine 80 and the three-way catalyst 81 are used to activate the activated carbon fiber 3
NO _x separated from No. 4 is reduced to harmless N ₂ and released outside the vehicle. That is, in the present embodiment, N taken from outside the vehicle
Since O _X is reduced to N ₂ and released, not only the air taken into the vehicle is purified, but also the air outside the vehicle is purified (minus emission).

Next, the operation of the automobile air purification apparatus 10 according to the first embodiment of the present invention will be described with reference to the flowcharts of FIGS. 4 to 6. A control device (not shown) of the automobile air purification device 10 turns on a start switch (not shown) by a driver (S10 returns Yes.
s) First, it is determined whether high humidity is detected by the humidity sensor 42 (S12). Here, when the humidity is below a certain level, it is determined whether or not the outside air introduction is set by the driver (S20). When the outside air introduction is set (Yes in S20), it is determined whether the second damper 22 is opened (S24). Here, when it is set to purify the air in the vehicle before and the outside air is not introduced (S24 is No), the second damper 22 is opened and the outside air is taken in from the outside air intake hole 12a (S25). ), The first damper 21 is closed, and the introduction of the air in the vehicle into the vehicle air purification device 10 is stopped (S26).

Then, it is judged whether or not the NO _X sensor 44 detects the NO _X concentration higher than a predetermined value (S42),
In the case of a predetermined value or less, that is, the silica gel 32 of the first column 30A or the second column 30B maintains the hygroscopic force, and
When the activated carbon fiber 34 maintains the NO _X adsorption force (No in S42), the blower 40 is normally rotated (S4).
4), the outside air is sent to the first column 30A or the second column 30B to purify NO _X and CO and introduce the NO _X and CO into the vehicle.

When it is determined in step 20 whether the outside air introduction is set or not, it is instructed to clean the air inside the vehicle, for example, it is set to clean the air smoked by one of the occupants. (S20
Is No), it is determined whether the first damper 21 is opened (S21). Here, when the outside air was previously set to be introduced (S21 is No), the first damper 21 is opened, the air in the vehicle is taken in from the inside air intake hole 11a (S22), and the second damper 22 is closed. Then, the introduction of outside air is stopped (S23).

On the other hand, when it is currently raining and the humidity is extremely high, the humidity sensor 42 detects the high humidity, and the determination in step 12 is Yes. At this time, the air control unit 84 is activated to start the dehumidifying operation (S14), and the first damper 21 and the second damper 2 are
After closing 2 (S15), it is determined whether outside air introduction is set (S30). When the outside air introduction is set (Yes in S30), the eighth damper 28 is opened and the seventh damper 27 is closed (S33, S34,
S35), the outside air sucked from the outside air intake pipe 17 is dehumidified by the evaporator 84a of the air control unit 84, and then pressure-fed to the first column 30A or the second column 30B, and the first and second columns 30A, 30B The decrease in hygroscopicity of the silica gel 32 is prevented.

Here, when it is judged in step 30 whether the outside air introduction is set or not, and the instruction is to clean the air in the vehicle (S30 is No), the seventh damper 2
7 is opened and the eighth damper 28 is closed (S3
1, S32, S33), the air in the vehicle sucked through the inside air intake pipe 16 is dehumidified by the evaporator 84a, and then pressure-fed to the first column 30A or the second column 30B. In the first embodiment, the evaporator 84a and the silica gel 32 are used together for dehumidification, but it is also possible to omit the silica gel 32 by always removing the humidity by the evaporator 84a. is there.

Here, if the determination in step 42 that the NO _X concentration is equal to or higher than a predetermined value is No, that is, when the hygroscopic capacity of the silica gel 32 is decreased, or the N of the activated carbon fiber 34 is N.
When the O _X adsorption power has decreased, the process proceeds to step 50, and heat treatment is performed on the silica gel 32 and the activated carbon fibers 34.
The heating process of step 50 will be described with reference to FIG. 5 showing a subroutine of the process.

First, the air cleaner 82 of the engine 80
The third damper 23, which opens and closes the exhaust pipe 19 leading to, is opened (S51). Then, the 1st, 2nd, 6th and 7th dampers 21, 22, 26, 27 for opening and closing the above-mentioned through holes 11a, 12a, 16, 17 for introducing the inside air or the outside air are closed (S52). Then, rotate the blower 40 in the reverse direction (S
53), the second column 30B (here, the second column 30
B is used for air purification, and the fourth damper 24 is operated so as to open the second column 30B as shown in the figure).
Pump to the side. Here, the heater wire 39 shown in FIGS. 3A and 3B is energized to separate water from the silica gel 32 and desorb NO _X from the activated carbon fiber 34 (S54). The desorbed water vapor and NO _x are sent to the engine 80 side, and the three-way catalyst 81 reduces the NO _{x to} nitrogen. If this heating is continued for the set 30 minutes, the judgment of step 55 whether the predetermined time has elapsed becomes Yes, the heating is stopped (S56), and the blower 40 is stopped (S56).
57), the third damper 23 is closed (S58), and the heating process ends.

Returning to the flowchart of FIG. 5 again, following the heat treatment (S50), the column is switched (S6).
0). This column switching process will be described with reference to FIG. 6 showing a subroutine of the process. First, it is determined whether the fourth damper 24 closes the first column 30A side (S61). Here, since the first column side is closed (S61 is Yes), the fourth column 24 is used to close the second column 30B (S62), and the sixth damper 26 is closed to complete the heat treatment. Second column 30B
Is set in the standby state, the fifth damper 25 is opened, and the first column 30A is made usable (S64). On the other hand, when the first column 30A is heated, the above step 61 is No, the first column 30A is closed by the fourth damper 24 (S65), and the fifth damper 25 is closed to close the first column. 30A is put into a standby state (S66). The column switching process (step 6 shown in FIG. 4) is performed by the above process.
0) is ended.

The second column 30B is formed by the above heat treatment.
4 becomes a standby state, the rotation of the blower 40 is started (S44) through the processing of steps 10 to 42 shown in FIG. 4, and the purification of air is started using the first column 30A.

In the first embodiment, since the air control unit 84 is used for dehumidification, there is an advantage that NO can be adsorbed by the activated carbon fiber 34 for a long time even in high humidity. In addition, the first column 30A and the second column 3
Since 0B is alternately regenerated and used, the purification of air can be continued for a long time without replacing the activated carbon fiber 34 and the silica gel 32. Further, since the silica gel 32 and the activated carbon fiber 34 are heated by the heater wire 39, there is an advantage that the cost can be reduced.

In the first embodiment, the first and second
Since the pressure feeding of air to the columns 30A and 30B and the pressure feeding of exhaust gas from the first and second columns 30A and 30B to the engine 80 are performed by rotating the single blower 40 in the forward and reverse directions, it is inexpensive. There is an advantage that can be configured.

Next, a second embodiment of the present invention will be described with reference to FIG. 2 (B) and FIGS. In the description of the second embodiment, the same reference numerals are used for the same members as in the first embodiment, and the description thereof will be omitted. FIG. 7 shows the configuration of the automobile air purification device 10 of the second embodiment, and FIG. 2 (B) shows the vehicle mounting position of the automobile air purification device 10.

In the first embodiment described above, dehumidification was performed using the air control unit 84 and the silica gel 32 in the first and second columns, but in the second embodiment, in the first and second columns. The humidity is reduced only by the zeolite 132 of the above. Therefore, FIG.
As shown in (B), the intake pipe 18 from the air control unit 84 is removed. Further, in the first embodiment, the silica gel 32 and the activated carbon fibers 34 are heated by using the heater wire, but in the second embodiment, the heating is performed by irradiating the microwave from the magnetron 46. ing. Furthermore, in the first embodiment, the air could not be purified while the column was being heated, but in the second embodiment, while the one column was being heated, the other column could be used to purify the air. It is configured.

In the first column 30A and the second column 30B, a dielectric container 33 that allows the electromagnetic waves from the magnetron 46 to pass therethrough is used. In the container 33, powdery zeolite 1 that adsorbs (deodorizes) water and ammonia 1
And 32, NO _X, and the activated carbon 134 for adsorbing harmful components of an internal combustion engine such as HC are accommodated. Activated carbon 134 is
As described above, it exhibits a good adsorptivity for NO _X. In addition, zeolite has a high adsorptivity for ammonia gas, which is a polar molecule, and water contained in the atmosphere. The content of ammonia gas in the air is N
O _X, a small amount with respect to HC. Therefore, in the first column 30A and the second column 30B, ammonia gas can be adsorbed by a small amount of zeolite. By disposing the zeolite 132 upstream of the activated carbon 134, the ammonia gas is adsorbed in advance by the zeolite 132, and then the remaining NO _X and HC are adsorbed by the activated carbon 134. The first column 30A and the second column 30B are shielded by a shield plate 62 that prevents the microwaves emitted from the magnetron 46 from leaking.

FIG. 8 shows a cross section taken along the line BB of FIG. The output from the magnetron 46 is transmitted through the waveguide 48 to the first column 3
0A or the second column 30B is irradiated. Switching of the microwave from the magnetron 46 to the first column 30A and the second column 30B is performed by the waveguide 48
Is performed by the switching device 50 provided in the. The switching device 50 is driven by a control device (not shown) that controls the first to sixth dampers 21, 22, 24, 25 and 26.

Next, the operation of the automobile air purification device 10 of the second embodiment will be described with reference to the flowchart of FIG. Here, as shown in FIG. 7, while the air is being purified in the second column 30B, the performance of the second column 30B is degraded, and the air purification is performed in the first column 30A and the regeneration operation of the second column 30B is performed. The operation when performing will be described as an example.

The control device uses the NO _X sensor 44 to
The NO _x concentration in the air purified by the first column 30A or the second column 30B is monitored. Here, when the zeolite 132 or the activated carbon 134 of the first column 30A and the second column 30B is deteriorated and the adsorption performance of NO, HC and the like is lowered, and the NO _X concentration becomes equal to or higher than the set value (S12).
2 is Yes), 4th damper 24 at 1st column 30A
It is determined whether the side is closed (S124). Here, since the first column 30A side is closed (S124 is Yes
s) First, the second column 30B side is closed by the fourth damper 24 (S126), and the pressure feeding of air to the second column 30B side is stopped to prepare for the regeneration operation. Then, the fifth damper 25 is opened (S128) to start the pressure-feeding of the purified air from the first column 30A through the air outlet pipe 13 into the passenger compartment. Then, the sixth damper 26 closes the air outlet pipe 13 side to prevent the inflow of NO _X generated during regeneration into the vehicle. Then, after switching the switching device 50 shown in FIG. 8, electric power is supplied from a vehicle-mounted battery (not shown) to cause the magnetron 46 to oscillate, and the microwave is applied to the second column 30B for 2 minutes (S132).

[0064] In the second column 30B, the Makuiro wave, NO _X adsorbed in the activated carbon 134, HC is disengaged, water and ammonia NH ₃ adsorbed in the zeolite 132 are disengaged. In the second embodiment, the NO _X separated by the blower 40 is not pressure-fed, but since negative pressure is generated by the intake cycle on the engine 80 side, this negative pressure sucks it out to the air cleaner 82 side. go. This desorbed water vapor, ammonia gas, N
O _X and HC are sucked into the engine 80, HC is burned in the combustion chamber, the NO _X is reduced to nitrogen by the three-way catalyst 81 in the same manner as in the first embodiment described above, and ammonia gas is It is turned into nitrogen and water vapor and then released into the atmosphere. By this heating operation, the activities of the zeolite 132 and the activated carbon 134 are restored, and it becomes possible to reuse them.
Fig. 1 shows the regeneration of activated carbon 134 by McIro waves.
See graph 4 above.

When the first column 30A is deteriorated, the above-mentioned step 124 becomes No and step 1
34, 136, 138, 140 at the first column 30A
Is reproduced. On the other hand, the automobile air purification device 10
When the power supply of is turned off (Yes in S141), the control device stops the control operation. In the second embodiment, since heating is performed using microwaves, there is an advantage that the zeolite 132 and the activated carbon 134 can be heated in a short time.

Further, in this second embodiment, the first and second
Since the exhaust gas from the columns 30A and 30B is sent to the engine 80 by using a negative pressure, there is an advantage that the device can be simplified and the cost can be reduced as compared with the case where a blower such as a blower is used.

Next, a third embodiment of the present invention will be described with reference to FIG. 2 (C), FIG. 10 and FIG.
FIG. 10 shows the configuration of an automobile air purification device 10 of the third embodiment, and FIG. 2 (C) shows the automobile air purification device 1
The mounting position of 0 on the vehicle is shown. In the first and second embodiments described above, the automobile air purification device 10 is arranged at the rear part of the vehicle, but in the third embodiment, it is housed in the engine room. Further, in the first and second embodiments described above, a pair of first and second columns 30A and 30B was used, but in the third embodiment, a single column 30 is used.
By using only this, it can be miniaturized and placed in the engine room.

Further, in the third embodiment, the column 30
The silica gel 32 and the activated carbon fiber 34 are heated by supplying the cooling water of the engine 80 to the water jacket 92 provided around the column 30 by switching the valve 83. Further, in the third embodiment, the automobile is configured to operate only when the inside air is circulated and the outside air is not introduced and the concentration of CO ₂ increases.

The operation of the automobile air purification apparatus 10 of the third embodiment will be described with reference to the flowchart of FIG. The vehicle air purification device 10 monitors the CO ₂ concentration in the vehicle by a CO ₂ sensor (not shown) (S72). Here, when the CO ₂ concentration reaches a predetermined value, for example, 3000 ppm or more (Yes in S72), it is determined whether internal air circulation is set in an air control device (not shown) (S74). Here, when the inside air recirculation is set (S74 is Yes), i.e., whether when the CO ₂ concentration is rising by an occupant of the respiration, the column 30 can adsorb NO _X, the NO _X sensor 44 N
Judgment is made based on whether or not the O _X concentration is below the set value (S7
6) When the NO _X concentration is below the set value (S76 returns N
o), rotate the blower 40 forward (S80), and use CO
And NO are purified and introduced into the vehicle to reduce the CO ₂ concentration. This operation is continued until the CO ₂ concentration in the vehicle becomes 3000 ppm or less (No in S72).

At this point, the adsorption force of the column 30 is reduced and N
When the O concentration is equal to or higher than the set value (Yes in S78), the column 30 is heated (S78). Here, the valve 83 is opened, the cooling water of the engine 80 is supplied to the water jacket 92 provided around the column 30, and the silica gel 32 and the activated carbon fiber 34 of the column 30 are heated. In the third embodiment, the cooling water that rises to about 100 ° is used, but instead of this, it is possible to heat the column 30 to a higher temperature by using the exhaust gas of the engine.

In the third embodiment, the activated carbon fiber 34 is used.
Since the adsorption of NO _{X by} the method is stopped to a necessary minimum, it is possible to operate the automobile air purification device 10 for a long period of time without using one piece of the activated carbon fiber 34 for replacement.

In the first, second and third embodiments described above, in order to oxidize CO, Pd is added to the activated carbon fiber 35.
Although the Pd catalyst 36 supporting C was used, a noble metal catalyst other than Pd can be used as long as it can oxidize CO. Further, the noble metal catalyst is not the activated carbon fiber 35 but pulverized activated carbon or It is also possible to support it on granular activated alumina or the like. Further, in the above-described embodiment, the activated carbon fibers 34 are folded and used in a pleat shape, but when the activated carbon fibers 34 having a large area are accommodated in the container, various folding methods can be used.

Further, in the above embodiment, the activated carbon fiber 3 is used.
NO _X at 4 and NO _X and HC at activated carbon 134,
Although the ammonia gas is adsorbed by the zeolite 132, various harmful gases can be adsorbed by using other adsorbents. Further, the harmful gas was separated from the adsorbent by heating with a heater or microwave, but other physical separation methods such as dissolving the harmful gas by passing water through the adsorbent and sending this solution to the engine 80 are adopted. You can also Furthermore, it is also possible to separate the harmful gas from the adsorbent by a chemical method using an acid, an alkali or the like instead of a physical method.

In the above-mentioned first, second and third embodiments,
N, which was not possible with conventional automobile air purification systems
O _X, to remove harmful gases such as CO may be introduced into the vehicle interior. Also, when traveling in an area with high NO _X and CO concentrations, if the internal air circulation is used, CO _{2 will be} emitted by the occupants' breath
Although the concentration is increased, in the above-described embodiment, it is possible to take in the purified outside air even when traveling in such an area, so that it is possible to prevent the increase in the CO ₂ concentration in the vehicle. In addition, activated carbon fibers 34 that remove harmful gases such as NO _x ,
Since the activated carbon 134 is heated and repeatedly used, air purification can be continued without performing maintenance for a long period of time.

Further, in the above-mentioned embodiment, the activated carbon fiber 34 is used by using the existing engine 80 and the three-way catalyst 81.
The NO _x separated from the above is reduced to harmless N ₂ and released outside the vehicle. That is, in the present embodiment, N taken from outside the vehicle
Since O _X is reduced to N ₂ and released to the outside of the vehicle, not only the air taken into the vehicle but also the air outside the vehicle (minus emission) can be purified.

[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. 2 is an explanatory view showing a mounting position of an automobile air purification device in each embodiment.

FIG. 3 (A) is a perspective view showing silica gel,
FIG. 3B is a perspective view of the activated carbon fiber, and FIG.
FIG. 4 is a perspective view of a Pd catalyst.

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

5 is a flowchart of the heat treatment shown in FIG.

6 is a flowchart of a column switching process shown in FIG.

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

8 is a cross-sectional view taken along line BB of the column shown in FIG.

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

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

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

FIG. 12 is a graph showing the results of a NO _x adsorption test.

FIG. 13 is a graph showing the results of NO adsorption test.

FIG. 14: NO by activated carbon fiber regenerated by heating
₆ is a graph showing the results of an _X adsorption test.

FIG. 15 is a graph showing the results of a CO adsorption test.

[Explanation of symbols]

 10 Automotive Air Purifier 30A First Column 30B Second Column 32 Silica Gel 34 Activated Carbon Fiber 36 Pd Catalyst 40 Blower 46 Magnetron 80 Engine 81 Three-way Catalyst 84 Air Control Unit

Claims (7)

[Claims] 1. An air containing a harmful gas is brought into contact with an adsorption member to adsorb the harmful gas and introduced into the vehicle. The harmful gas is separated from the adsorption member by a physical or chemical method, and separated from the adsorption member. The harmful gas is sent to an engine equipped with an exhaust gas purification device, and the adsorption member that has desorbed the harmful gas is brought into contact with air containing the harmful gas to adsorb the harmful gas again. Purification method. 2. The air containing the harmful gas outside the vehicle is brought into contact with the adsorption member to adsorb the harmful gas, and then introduced into the vehicle, and the harmful gas is separated from the adsorption member by a physical or chemical method, The harmful gas separated from the adsorption member is sent to an engine equipped with an exhaust gas purification device, and the adsorption member separated from the harmful gas is brought into contact with air containing the harmful gas to adsorb the harmful gas again. Air purification method for automobiles. 3. An NO _X adsorbing member mainly composed of activated carbon, and air outside the vehicle containing NO _X is sent to the adsorbing member to supply N _X.
Blower means for introducing air having adsorbed O _X into the vehicle, and heating means for heating the adsorbent member on which the NO _X adsorbing operation has been performed by the air blower member and for desorbing NO _X adsorbed by the adsorbent member. And an exhaust gas feed means for sending NO _X separated from the adsorption member by the heating means to an engine equipped with an exhaust gas purification apparatus. 4. A container accommodating a NO _x adsorbing member mainly composed of activated carbon and a noble metal catalyst having an oxidation-reduction ability, and air outside the vehicle containing NO _x and CO is sent into the container, and NO is fed to the activated carbon. with the adsorption of _X, heated and blowing means for introducing air to oxidize the CO to CO ₂ in a noble metal catalyst in the vehicle, the suction member of the vessel suction operation of the NO _X was made by the blowing means, A heating means for releasing the NO _x from the adsorbing member, and an exhaust feed means for sending the NO _x detached from the adsorbing member by the heating means to an engine equipped with an exhaust purification device. Air purifying device for automobiles. 5. The air purification apparatus for an automobile according to claim 3, wherein the activated carbon is made of activated carbon fiber. 6. The air purifying apparatus for an automobile according to claim 3, wherein the blower means and the exhaust feed means are driven by a single motor. 7. The exhaust gas sending means sends NO _X to the engine by the negative pressure of the engine.
Or the automobile air purification device of 4.