JP2002349229A - Exhaust gas treating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an exhaust emission control device capable of purifying both NOx and particulate matters in exhaust gas by carrying an NOx absorber and a catalyst in a filter member for collecting particulate matters, and miniaturizing a high frequency oscillator and its power supply for generating microwaves for regenerating the NOx absorber, the catalyst and the filter member. SOLUTION: The exhaust emission control device 1 purifying both the NOx and the particulate matters in the exhaust gas G of an engine is formed of the filter member 40 carrying the NOx absorber 41, the catalyst 42, and particles 43 formed of a material with large electric conductivity, and a regenerating device 50 provided with a microwave generator 51. It is composed so as to guide the microwaves generated by the microwave generator 51 by a waveguide 51b and irradiate them on the filter member 40.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exhaust gas purifying apparatus for purifying nitrogen oxides (NOx) and particulate matter (PM) in exhaust gas from an internal combustion engine, a combustion device, or the like. More specifically, the present invention relates to an exhaust gas purifying apparatus that irradiates a filter member carrying a NOx absorbent and a catalyst with microwaves.

[0002]

2. Description of the Related Art In order to reduce and remove nitrogen oxides (NOx) from exhaust gas from mobile internal combustion engines such as automobiles and stationary internal combustion engines, NOx reduction catalysts and three-way catalysts are used. However, when exhaust gas of a diesel engine is targeted, the three-way catalyst cannot be used because the oxygen concentration in the exhaust gas is high, and a NOx reduction catalyst is mainly used.

As the NOx reduction catalyst having a direct NOx decomposition action, metal ion-substituted zeolites, perovskites, brown miralites and noble metal catalysts are used. These catalysts have a high NOx purification ability, but have a high NOx purification capacity. Since the part remains in the catalyst as nitrate or nitrite, the life of the catalyst is shortened and deteriorated.

[0004] Further, there is also an apparatus or method for recovering the NOx absorbing ability by purifying the exhaust gas by absorbing the NOx at the time of trapping, using a NOx absorbing material, and performing a regeneration process when the NOx absorbing ability is reduced. Research and development.

[0005] Regarding regeneration of these NOx reduction catalysts and NOx absorbents, a high voltage is applied to electrodes sandwiching a carrier for carrying the NOx reduction catalysts and NOx absorbents to generate plasma, which is disposed between the electrodes. It has been proposed to activate and regenerate the exhausted catalyst and NOx absorbent to improve the exhaust gas purification ability.

On the other hand, a method of using plasma in purifying exhaust gas has been researched and developed. By applying a high voltage to the electrodes and activating a catalyst disposed therebetween, the exhaust gas purifying ability is improved. Purification apparatuses have been proposed in Japanese Patent Application Laid-Open Nos. 5-49939, 10-268632, 4-244216, and the like.

In the exhaust gas purifying apparatus disclosed in Japanese Patent Application Laid-Open No. 5-49939, a microwave generated by a high-frequency oscillator is guided to a purifying means in which a radio wave absorber and a catalyst are carried on a ceramic carrier at the same time when the engine is started. Microwaves are propagated through the tube and irradiated with microwaves. This microwave energy is absorbed by the radio wave absorber carried by the purifying means, and the purifying means is rapidly heated in a short time. The aim is to reduce substances.

In this exhaust gas purifying device, the use of a waveguide for propagating microwaves widens the selection range of the arrangement position of the high-frequency oscillator, and absorbs the microwaves with a radio wave absorber carried together with a catalyst. Therefore, there is an advantage that microwaves can be efficiently converted to heat energy.

In the exhaust gas purifying apparatuses disclosed in Japanese Patent Application Laid-Open Nos. 10-266832 and 4-244216, a positive discharge electrode is provided on the upstream end surface of the catalyst carrier, and a negative discharge electrode is provided on the downstream end surface. By applying a high frequency and high voltage, harmful components in the exhaust gas are converted into a plasma state of positive ions and negative ions to be decomposed to reduce harmful substances in the exhaust gas.

In the exhaust gas treatment apparatus disclosed in Japanese Patent Application Laid-Open No. 4-244216, an upstream side of the plasma generating electrode is provided.
Inject diluent gas such as nitrogen gas, argon gas or air,
By reducing the NOx concentration, the denitration rate is improved.

[0011]

However, in the first exhaust gas purifying apparatus disclosed in Japanese Unexamined Patent Publication No. 5-49939, the microwave irradiation aims at increasing the temperature by the radio wave absorber only at the time of a cold start. Since the honeycomb structure is used to support the catalyst and the radio wave absorber, there is a problem that the particulate matter in the exhaust gas is not taken into account, and the particulate matter cannot be purified. Since the entire structure is simultaneously irradiated with microwaves, a high-frequency oscillator having a large output and a power supply are required, and there is a problem that the device becomes large.

[0012] In the case of the exhaust gas purifying apparatus utilizing the discharge from the electrode plate disclosed in Japanese Patent Application Laid-Open Nos. 10-266832 and 4-244216, it is difficult to generate uniform plasma. However, there is a problem that harmful substances in the exhaust gas cannot be efficiently decomposed.

Further, when a diluent gas is used as in an exhaust gas purifying apparatus disclosed in Japanese Patent Application Laid-Open No. 4-244216,
There is a problem that a diluent gas and a diluent gas supply device are required, and the amount of exhaust gas discharged increases.

In addition, in order to purify the exhaust gas of a diesel engine, NOx contained in the exhaust gas and particulate matter (particulate carbon fine particles, liquid or solid high In the prior art, it is necessary to dispose both a NOx removal device and a particulate matter removal device such as a DPF (diesel particulate filter) in the exhaust passage. There has been a problem of an increase in the size of the device and the accompanying cost.

Further, the NOx removal device is capable of removing SOx in exhaust gas.
Therefore, in a diesel engine using a fuel having a relatively high sulfur component, the sulfur poisoning becomes a problem, and there is a problem that it is difficult to use the NOx removing device.

The present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide a filter member for trapping particulate matter, which carries a NOx absorbent and a catalyst, and forms an exhaust gas. NOx and particulate matter can be purified together,
In addition, a high-frequency oscillator for generating microwaves for regenerating the NOx absorbent, the catalyst and the filter member and its power supply can be miniaturized, and the compact, energy-efficient regeneration of the NOx absorbent, the catalyst and the filter member which have lost their activity can be performed It is an object of the present invention to provide an exhaust gas purifying apparatus capable of performing the above.

A further object is to remove NOx and particulates at the same time, and to reduce SOx
An object of the present invention is to provide an exhaust gas purifying apparatus which is hardly poisoned by the exhaust gas.

[0018]

SUMMARY OF THE INVENTION An exhaust gas treatment apparatus and an exhaust gas treatment method for achieving the above-mentioned object are as follows.
It is configured as follows.

1) A filter device in which a filter member for trapping particulate matter in exhaust gas carries a NOx absorbent for absorbing and reducing and purifying NOx and a catalyst, and regeneration for regenerating the NOx absorbent and the catalyst An exhaust gas purifying apparatus disposed in an exhaust path of an engine and purifying both NOx and particulate matter in exhaust gas, wherein the filter member carries particles formed of a material having a high electric conductivity. At the same time, the reproducing apparatus is provided with a microwave generator, and the microwave generated by the microwave generator is guided by a waveguide to irradiate the filter member.

According to this configuration, the filter member allows
It is possible to purify by collecting and oxidizing and removing the particulates, and to purify by adsorbing and reducing NOx by the NOx absorbent and the catalyst.

Then, the microwave generated by the microwave generator of the reproducing apparatus is guided by the waveguide and irradiated on the filter member, so that the action of the particles formed of the material having high electric conductivity such as the metal particles can be achieved. This makes it possible to efficiently activate and regenerate a NOx absorbent whose absorption capacity has decreased or a catalyst that has deteriorated due to sulfur poisoning, etc., and that the collected particulates can be efficiently generated. Can also be regenerated by removing it by oxidation.

2) In the exhaust gas purifying apparatus described above, the range in which the filter member can be irradiated with microwaves at the same time is limited to a part of the filter member, and the part to be irradiated with microwaves or the microwave is irradiated. The whole of the filter member is irradiated with the microwave while moving the part or switching the part irradiated with the microwave and the part not irradiated with the microwave sequentially or alternately.

That is, NOx in the exhaust gas is absorbed or reduced and purified by the NOx absorbing material or the catalyst in the portion not irradiated with the microwave, and when the NOx absorbing ability or catalytic action of the NOx absorbing material is reduced, When the activity of materials and catalysts declines, microwaves
Recovers and restores absorption capacity and catalytic activity.

According to this configuration, the microwave is applied to a limited portion of the filter member supporting the NOx absorbent and the catalyst, and the portion to be irradiated with the microwave is changed with time, so that the microwave is irradiated for a predetermined time. Since the entire filter member can be irradiated with microwaves every time, the high-frequency oscillator having a small output and its power supply can activate and regenerate the NOx absorbent and the catalyst of the entire filter member.

Therefore, it is possible to continuously remove NOx in the exhaust gas and regenerate the NOx absorbent and the catalyst,
In addition, the size of the microwave generator can be reduced.

Since the temperature of the filter member rises due to the irradiation of the microwave, the particulate matter trapped in the filter member is also burned and removed. Regarding regeneration of filter members,
This can be done continuously.

3) In the exhaust gas purifying apparatus described above, the regenerating device is provided with a magnetic field generating device for applying a magnetic field to the filter member. Can be generated, and the electrons discharged by the microwave discharge (electron cyclotron resonance plasma) generated from the resonance can be used to purify the NOx component,
Absorbers and catalysts can be regenerated.

The magnetic field generator for applying the magnetic field can be formed by a solenoid or a permanent magnet provided on the outer peripheral portion of the filter member.

4) The exhaust gas processing apparatus described above is provided with exhaust gas inflow prevention means for preventing the exhaust gas from flowing into the portion of the filter member to which the microwave is irradiated, so that NOx absorption is achieved. Exhaust gas flowing in at the time of recovery of the activity of the material can be shut off.

When the plasma is generated under the flow of the exhaust gas, oxygen is present in the exhaust gas, and the regeneration of this oxygen proceeds preferentially. Although NOx increases, the residual oxygen in the exhaust gas in the vicinity of the NOx absorbent is almost consumed by shutting off the exhaust gas.
The NOx absorbent can be regenerated while reducing Ox.

When plasma is generated in a state where exhaust gas is flowing, gas components not related to purification are also turned into plasma, which consumes a large amount of energy. Since the microwaves are radiated in a state in which the operation is stopped, the energy consumption can be reduced.

5) In the exhaust gas treatment apparatus described above, the regenerating apparatus is provided with a heating means for heating the filter member, and the heating means is provided with an electric heating device, a high-frequency dielectric heating device, a microwave heating device. By forming any one or a combination thereof, the filter member and the NOx absorbent and the catalyst carried on the filter member can be heated.

Therefore, since the role of heating can be shared by the heating means, the microwave generator and its power supply can be further miniaturized.

6) In the above exhaust gas treatment apparatus,
The NOx absorbent is made of an adsorbent such as activated carbon or zeolite,
alkaline earth metal oxides such as gO, CaO, BaO, C
eO _TwoRare earth oxides such as TiO_TwoSuch as titanium oxide,
ZrO_Two, Al_TwoO_ThreeAny one or a combination of
Form. With the NOx absorbent having this configuration, N
Ox can be absorbed and its NOx absorption ability by microwave irradiation etc.
Can regenerate power.

7) In the above exhaust gas treatment apparatus, the catalyst is formed of at least one of a group VIII element, a group Ib element, a rare earth oxide, or a combination thereof in the periodic table. In other words, at least one of rare earth oxides which are oxides of Group VIII (iron group, platinum group), group Ib (copper group), scandium Sc, yttrium Y, or the like of the periodic table, or the like. Form with the mixture. Here, for example, a combination in the same group such as a combination of iron Fe and ruthenium Ru in the group VIII is also included.

8) In the above exhaust gas treatment apparatus, the filter member is formed of any one of a fiber, a porous body, and a honeycomb having a ceramic fine particle layer on the surface, or a combination thereof. Due to the ceramic fine particle layer provided on the surface of the filter member, the surface area that can be supported is dramatically increased, and the mechanical holding capacity of the NOx absorbent and the catalyst is increased, thereby improving the durability. .

9) In the above exhaust gas treatment apparatus, the filter member is formed by combining a plurality of divided honeycomb members with a buffer material interposed therebetween, and holding the filter member in a storage container. By doing so, it is possible to prevent the honeycomb member from being broken by thermal expansion.

[0038]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an exhaust gas treatment apparatus according to an embodiment of the present invention will be described with reference to the drawings.

As shown in FIGS. 1 and 2, this exhaust gas treatment apparatus 1 comprises a filter device 4 having a filter member 40 carrying a NOx absorbent 41, a catalyst 42 and metal particles 43, and a regenerating device 50. And arranged in the exhaust passage 2 of the diesel engine of the vehicle.

The filter member 40 of the filter device 4
1 and 2 are made of a ceramic honeycomb 40a, but are made of ceramic or metal fiber, porous body, or the like.
Any one of the honeycombs or a combination thereof can be used. In addition, a fine particle layer of ceramics is formed on the surface of the filter member 40 to increase the surface area that can be supported.

The filter member 40 is formed of a plurality of (six in FIG. 2) honeycomb members 40a, and ceramic fibers and ceramic fibers are interposed between the honeycomb members 40a.
A cylindrical filter member 40 having a hollow portion is formed by assembling around a hollow ceramic cylinder 40e with a buffer material 40b formed of a ceramic whisker or the like interposed therebetween. A heat insulating material 4 for keeping heat is provided around the filter member 40.
d and a solenoid 53 for applying a magnetic field are provided and housed in an outer cover (housing container) 4c. With this configuration,
The honeycomb member 40a is prevented from being broken by thermal expansion.

The NOx absorbent 41 supported on the filter member 40 is formed of activated carbon here. However, other than activated carbon, adsorbents such as zeolite, alkaline earth metal oxides such as MgO, CaO and BaO, CeO ₂ Or other rare earth oxides, titanium oxide such as TiO ₂ , ZrO ₂ , Al ₂ O ₃
, Or a combination thereof.

The catalyst 4 carried on the filter member 40
Here, 2 is formed of Rh, Pt, and Ni, but can be formed of at least one of an element of Group VIII, an element of Group Ib, and a rare earth oxide of the periodic table, or a combination thereof. .

The particles 43 of a material having high electric conductivity carried on the filter member 40 are formed of metal particles such as Fe and Ni, but may be iron oxide or ferrite.

Next, in the present invention, the reproducing device 50 is formed with the microwave generating device 51, and the microwave generated by the magnetron (microwave oscillation tube) 51a of the microwave generating device 51 is guided. It is configured to be guided by the tube 51b and irradiate the filter member 40.

The output of the magnetron 51a is controlled by a magnetron output control unit 60 which inputs the detection values of temperature sensors 61 and 62 such as thermocouples provided at the inlet 4a and the outlet 4b of the exhaust gas of the filter device 4, respectively. Done.

The waveguide 51a is connected to the filter member 40.
And is rotatably formed in the hollow ceramic cylinder 40e by a motor 51d driven by a motor power supply 51c.

The waveguide 51a has an outer peripheral reflecting surface 51.
A part of ba is omitted along the axial direction to have a radiation port 51bb, from which microwave is radiated in a wedge shape (V part in FIG. 2) in cross-sectional view, and is guided. Tube 5
By rotating the shaft 1a around the axis 51bc, the entire filter member 40 can be sequentially irradiated with microwaves. If the outer cover 4c is formed of a material that can reflect microwaves, the microwaves can be confined in the outer cover 4c, so that the effect of microwave irradiation can be increased.

The tip side of the shaft 51bc of the waveguide 51a,
That is, a ceramic plate 52 is provided on the inflow side of the exhaust gas G of the filter member 40 to serve as exhaust gas inflow prevention means for stopping the inflow of the exhaust gas G into the portion V of the filter member 40 where the microwave is irradiated. The ceramic plate 52 that rotates together with the waveguide 51a blocks the flow of the exhaust gas G into the portion V to be irradiated with the microwave, thereby preventing the generation of NOx and improving the energy efficiency.

Further, at the time of microwave irradiation, a configuration is made such that a current can flow through a solenoid 53 disposed on the outer periphery of the filter member 40a to generate a magnetic field. By applying a magnetic field to the filter member 40a, an electron cyclotron resonance plasma generated by the cyclotron motion of the electrons and the resonance of the microwave can be used. 42 can be efficiently regenerated, and the NOx removal mechanism by electrons as shown in FIG.
Purification can be promoted. M in FIG. 3 is VI
It indicates an element of Group II and Group Ib.

Although not shown, the reproducing apparatus 50 is formed of, for example, an electric heater such as an electric heater between the filter members, a high-frequency dielectric heater, a microwave heater, or the like. The microwave generator and the power source thereof can be further miniaturized by being formed with a heating means and having the heating means share the role of heating the filter member 40.

Next, a control flow of the exhaust gas purifying apparatus having the above configuration will be described with reference to FIG.

In the control flow of FIG. 4, when started, the apparatus is operated in step S11, a microwave is oscillated from the magnetron 51 by the magnetron output control unit 60, and the motor 51d is driven to drive the waveguide 51b. And the ceramic plate 52 is rotated.

Then, the microwave output control in steps S12 to S17 is performed, and upon receiving the device stop command, the process goes from step S18 to step S19, where the device is stopped and the control is terminated.

In steps S12 to S17, first,
In step S12, the exhaust gas inlet temperature and the exhaust gas outlet temperature are input from the temperature sensors 61 and 62, the output for controlling the magnetron 51a is read, and the catalyst temperature T is calculated.

Then, at step S13, the catalyst temperature T becomes 7
If it is determined that the temperature is higher than 00 ° C., the output of the magnetron 51a is reduced (decreased) by a predetermined amount in step S17, and the process goes to step S18. If it is determined that the catalyst temperature T is 700 ° C. or less, the process proceeds to step S14. Then, it is determined whether the catalyst temperature T is higher than 650 ° C.

In this step S14, the catalyst temperature T becomes 65
If it is determined that the temperature is higher than 0 ° C., the output of the magnetron 51a is maintained without changing in step S16,
Go to step S18. If the catalyst temperature T is determined to be 650 ° C. or lower, the magnetron 5 is determined in step S15.
1a is increased (increased) by a predetermined amount, and step S
Go to 18.

In step S18, it is determined whether or not a device stop command has been issued. If not, the process returns to step S12 and repeats steps S12 to S18. If the apparatus stop command has been issued, the apparatus stops the microwave oscillation in the magnetron 51 and the drive of the motor 51d in step S19, and ends the control.

With this control, the catalyst temperature T is maintained in the optimum temperature range (650 ° C. to 700 ° C.) for purification and regeneration.
The NOx absorbent 41, the catalyst 42, and the filter member 40 are regenerated.

Next, the exhaust gas processing by the exhaust gas processing apparatus 1 having the above configuration will be described.

When the exhaust gas G flows into the exhaust gas processing apparatus 1, the exhaust gas G flows into the honeycomb member 40a not covered by the ceramic plate 52, and the NOx component in the exhaust gas G is reduced by the NOx absorber. The particulate matter in the exhaust gas is collected or purified by the honeycomb member 40a.

Then, in this trapping state, the waveguide 51b is rotated at a low speed (about one rotation in 60 seconds) while irradiating the microwave by operating the reproduction processing device 51, and the ceramic plate 52 is rotated. The NOx absorber 41, the catalyst 42, and the filter member 40a in a portion covered with the exhaust gas G and blocked from flowing in are activated and regenerated.

At the same time, a current is applied to the solenoid 53 to apply a magnetic field, and the catalyst temperature T is maintained in the range of 650 ° C. to 700 ° C. by control according to the control flow of FIG.

The NOx absorber 41 and the catalyst 42 are activated and regenerated by the electron cyclone resonance plasma generated by the microwave irradiation and the application of the magnetic field, and are collected and deposited on the filter member 40 by maintaining the high temperature state. The particulate matter is burned off and the filter member 40 is regenerated. It should be noted that the maintenance of this high temperature state allows the NOx absorber 4
1 and the sulfur component poisoning the catalyst 42 are also burned off.

According to the exhaust gas purifying apparatus 1 having the above structure, NOx contained in the exhaust gas G can be reduced and purified by the NOx absorbent 41 and the catalyst 42, and particulate matter is also captured by the filter member 40. Can be removed.

Then, the catalyst temperature T is maintained in the range of 650 ° C. to 700 ° C. by microwave irradiation, so that the NOx absorbent 41, the catalyst 42, and the filter member 40a can be regenerated.

Further, by applying a magnetic field during microwave irradiation, electron cyclotron resonance plasma can be used, and the electrons emitted at this time can be used to regenerate the NOx absorbent 41 and the catalyst 42. The removal of NOx can be promoted.

The ceramic plate 52 allows the exhaust gas G to reach a portion of the filter member 40 where microwaves are irradiated.
Can be cut off to create a reducing atmosphere and promote NOx reduction purification, and the input energy for microwave irradiation can be reduced. In particular, by removing NOx in a reducing atmosphere generated by CO obtained by oxidizing the particulate matter, the particulate matter and NOx can be simultaneously purified.

[Embodiment] Next, the result of a test performed by the above exhaust gas purifying apparatus will be described.

In this embodiment, the NOx absorbent is
O, BaO and CeO ₂ , TiO ₂ , ZrO ₂ , Al ₂ O
Forming a mixture of _3, Pt as a major composition of the catalyst and the electric conductivity (platinum), Ru (ruthenium), using a Rh (rhodium) was an exhaust gas purification device carrying them honeycomb.

The exhaust gas from the engine was passed through the exhaust gas purifier to remove NOx and to collect particulate matter.

Thereafter, the waveguide was rotated while irradiating a microwave of 2450 Hz. As a result, while partially irradiating the microwaves on the honeycomb supporting the NOx absorbent and the catalyst, the irradiated portions were moved to irradiate the entire microwave.

Further, the front surface of the honeycomb where the microwaves are irradiated is covered with a ceramic plate to prevent exhaust gas from flowing during microwave irradiation.
A magnetic field of about 875 G was applied, thereby generating an electron cyclotron resonance plasma.

Further, the output of microwaves is controlled by the catalyst temperature to maintain the temperature of the catalyst in the range of 650 ° C. to 700 ° C. to regenerate the NOx absorbent, decompose NOx, and oxidize and remove particulate matter. Was.

In this test, it was found that the NOx removal rate was 85% and the particulate (particulate matter) removal rate was 75%. The NOx removal rate after 500 hours was 83%, and the result was that almost no decrease in performance due to SOx poisoning was observed.

[0076]

As described above, according to the exhaust gas treatment apparatus of the present invention, the following effects can be obtained.

Since the exhaust gas is purified by carrying a NOx absorbent and a catalyst on a filter member for trapping particulate matter (particulates), the particulate matter can be trapped and removed by the filter member. By the absorbent and the catalyst, N
Ox can be absorbed and reduced and purified.

Then, the microwave generated by the microwave generator of the reproducing apparatus is guided by the waveguide and irradiated on the filter member, so that the action of particles formed of a material having a high electric conductivity such as metal particles is performed. As a result, a stable plasma can be generated, and this plasma can efficiently activate and regenerate a NOx absorbent whose absorption capacity has decreased, or a catalyst that has deteriorated due to sulfur poisoning, etc. Substances can also be regenerated by oxidative removal.

Further, by irradiating a microwave to a limited portion of the filter member carrying the NOx absorbent and the catalyst and changing the portion to be irradiated with the microwave with time, the filter member is fixed at regular intervals. Since the whole can be irradiated with microwaves, the activation and regeneration of the NOx absorber and the catalyst of the entire filter member can be performed with a high-frequency oscillator having a small output and its power supply, so that the microwave generator can be downsized. .

Further, by applying a magnetic field to the filter member, a microwave discharge (electron cyclotron resonance plasma) generated by the cyclotron motion of the electrons and the resonance of the microwave can be used. , NOx removal and catalyst component regeneration can be performed efficiently.

Then, the flow of exhaust gas to the portion of the filter to be irradiated with microwaves is cut off to create a reducing atmosphere, thereby reducing NOx efficiently while purifying NOx.
Since the x-absorber and the catalyst can be regenerated, and the flow of the exhaust gas is stopped when irradiating the microwave, the input energy can be reduced.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a configuration of an exhaust gas purifying apparatus according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG. 1 showing a configuration of the exhaust gas purification device.

FIG. 3 is a view showing a mechanism of removing NOx by electrons.

FIG. 4 is a diagram showing an example of a regeneration control flow of the exhaust gas purification device according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Exhaust gas processing apparatus 2 Exhaust passage 40 Filter member 41 NOx absorbent 42 Catalyst 43 Particles formed of a material having high electric conductivity 50 Regeneration device 51 Microwave generator 51b Waveguide 53 Solenoid (magnetic field generator) G Exhaust Gas V Microwave irradiation range

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3G090 AA02 BA08 DA12 3G091 AA02 AA18 AB06 AB13 BA01 BA14 CA05 EA17 EA18 FC01 GA04 GA05 GA06 GB03Y GB04W GB04Y GB05W GB06W GB09Y GB10Y GB17Y

Claims (9)

[Claims] 1. A filter device in which a filter member for trapping particulate matter in exhaust gas carries a NOx absorbent for absorbing and reducing and purifying NOx and a catalyst, and regeneration for regenerating the NOx absorbent and the catalyst. An exhaust gas purifying apparatus disposed in an exhaust path of an engine and purifying both NOx and particulate matter in exhaust gas, wherein the filter member carries particles formed of a material having a high electric conductivity. Exhaust gas treatment, wherein the regenerating device is provided with a microwave generator, and the microwave generated by the microwave generator is guided by a waveguide to irradiate the filter member. apparatus. 2. A range in which microwaves can be simultaneously irradiated on the filter member is limited to a part of the filter member, and a portion to be irradiated with microwaves or a portion to be irradiated with microwaves is moved, or The exhaust gas processing apparatus according to claim 1, wherein microwaves are applied to the entire filter member while sequentially or alternately switching a portion to be irradiated and a portion to which microwaves are not applied. 3. The exhaust gas treatment apparatus according to claim 1, wherein the regenerator includes a magnetic field generator that applies a magnetic field to the filter member. 4. The apparatus according to claim 1, further comprising exhaust gas inflow prevention means for preventing inflow of exhaust gas into a portion of the filter member to be irradiated with microwaves. Exhaust gas treatment device. 5. The regenerating apparatus is provided with a heating means for heating a filter member, and the heating means is any one of an electric heating device, a high-frequency dielectric heating device, and a microwave heating device or a combination thereof. The exhaust gas treatment device according to any one of claims 1 to 4, wherein the exhaust gas treatment device is formed by: 6. The NOx absorbent comprises an adsorbent such as activated carbon and zeolite; an alkaline earth metal oxide such as MgO, CaO and BaO; a rare earth oxide such as CeO _2; a titanium oxide such as TiO ₂ ; _2, claim and forming either one or a combination of Al ₂ O _3. 1 to
The exhaust gas treatment device according to any one of claims 6 to 13. 7. The catalyst according to claim 1, wherein the catalyst is an element of group VIII of the periodic table,
7. The semiconductor device according to claim 1, which is formed of at least one of a group Ib element and a rare earth oxide, or a combination thereof.
An exhaust gas treatment device according to any one of the preceding claims. 8. The filter member according to claim 1, wherein the filter member is formed of any one of a fiber, a porous body, and a honeycomb having a ceramic fine particle layer on the surface, or a combination thereof. An exhaust gas treatment device according to item 1. 9. A honeycomb member obtained by dividing the filter member into a plurality of members is formed by interposing a cushioning material therebetween.
The exhaust gas treatment device according to any one of claims 1 to 8, wherein the filter member is held in a storage container.