WO2011043046A1 - Exhaust gas purification device - Google Patents

Abstract

An exhaust gas purification device comprising a diesel particulate filter, an electric heater for regeneration purposes, and an air-blowing unit, wherein the diesel particulate filter carries an oxidation catalyst, the diesel particulate filter and the electric heater for regeneration purposes that can be driven by an external power source are arranged close together, and an opening-closing unit that enables the installation and removal of the air-blowing unit in an exhaust gas passage is provided in such a manner that the air-blowing unit is removed from the opening-closing unit when a diesel engine is operated and is connected to the opening-closing unit when the diesel engine is stopped.

Description

Exhaust gas purification device

The present invention relates to an exhaust gas purifying apparatus that collects and burns away particulates contained in exhaust gas of a diesel engine or the like.

The conventional exhaust gas purification device regenerates the particulates collected in the diesel particulate filter using the period when the diesel engine is stopped. Such an exhaust gas purification apparatus generally includes a diesel particulate filter, an electric heater for regeneration, and a blowing means. Here, the diesel particulate filter collects particulates contained in the exhaust gas of the diesel engine. The electric heater for regeneration burns and removes the particulates collected by the diesel particulate filter. The air blowing means sends air for regeneration to the diesel particulate filter.

Such an exhaust gas purification device has a problem in miniaturization of the device because the air blowing means is incorporated. On the other hand, there has been proposed an exhaust gas purifying apparatus that realizes downsizing by sharing a blower for indoor ventilation of a vehicle and a blowing means for sending air for regeneration to a diesel particulate filter ( For example, see Patent Document 1).

Hereinafter, the exhaust gas purification device will be described with reference to FIG.

FIG. 12 is a side view of a conventional exhaust gas purification device. The exhaust gas purification device 101 includes a diesel particulate filter 104, a regeneration electric heater 105, and a blowing means 106. Here, the diesel particulate filter 104 collects the particulates 103 contained in the exhaust gas of the diesel engine 102. The regeneration electric heater 105 burns and removes the particulates 103 collected by the diesel particulate filter 104. The air blowing means 106 sends air for regeneration to the diesel particulate filter 104.

The blower means 106 shares a blower for sending air for regeneration to the diesel particulate filter 104 and a blower for ventilating the interior 108 of the vehicle 107. Further, the exhaust gas purification apparatus 101 includes switching means 109 that sends the air blown from the air blowing means 106 to the interior 108 side of the vehicle 107 and the diesel particulate filter 104 side.

The exhaust gas purification apparatus 101 can be downsized by sharing the air blowing means 106 for sending the air for regeneration to the diesel particulate filter 104 and the blower for ventilating the room 108 in the vehicle 107. However, the exhaust gas purifying apparatus 101 requires a switching unit 109 and a control unit for controlling the amount of air blown by the air blowing unit 106 separately. Some types of vehicles are not equipped with a blower for indoor ventilation, and the exhaust gas purification device 101 has a narrow application range.

In addition, in order to burn and remove the particulate 103, it is necessary to raise the temperature of the particulate 103 to about 600 ° C. to 650 ° C., which is a flammable temperature, using the electric heater 105 for regeneration. For this reason, the exhaust gas purification device 101 as a whole has been increased in size by a heat insulating structure for keeping the diesel particulate filter 104 warm, a high-output electric heater 105 for regeneration, and the like.

Therefore, there was a problem that further miniaturization was difficult.

JP-A-6-117219

The present invention includes a diesel particulate filter that collects particulates in exhaust gas in an exhaust passage of a diesel engine, an electric heater for regeneration that burns and removes particulates collected by the diesel particulate filter, and a blower unit. The diesel particulate filter carries an oxidation catalyst, and the diesel particulate filter and an electric heater for regeneration driven by an external power source are arranged close to each other, and the air blower is driven by an external power source and is connected to the exhaust passage. An opening / closing part that makes the air blowing part detachable is arranged, the air blowing part is removed from the opening / closing part when the diesel engine is operated, the air blowing part is connected to the air opening / closing part when the diesel engine is stopped, and the electric heater for regeneration by the air blowing part is connected to the diesel particulate filter Regenerated sky heated by Blowing.

As a result, only when it is necessary to burn and remove the collected particulates, the blower is attached to the opening / closing part, so that a more compact exhaust gas purification device can be provided.

FIG. 1 is a side view of an exhaust gas purification apparatus according to Embodiment 1 of the present invention. FIG. 2 is a perspective view of the regeneration electric heater of the exhaust gas purifying apparatus according to the second embodiment of the present invention. FIG. 3 is a side view of the exhaust gas purification apparatus according to Embodiment 3 of the present invention. FIG. 4 is a side view of the exhaust gas purification apparatus according to Embodiment 4 of the present invention. FIG. 5 is a side view of the exhaust gas purification apparatus according to Embodiment 5 of the present invention. FIG. 6 is a configuration diagram showing a control unit of the exhaust gas purification device. FIG. 7 is a side view of the exhaust gas purifying apparatus according to Embodiment 6 of the present invention. FIG. 8 is a side view of the exhaust gas purification apparatus according to Embodiment 7 of the present invention. FIG. 9 is a side view of the exhaust gas purifying apparatus according to the eighth embodiment of the present invention. FIG. 10 is a side view of the exhaust gas purifying apparatus according to Embodiment 9 of the present invention. FIG. 11 is a side configuration diagram of an exhaust gas purification apparatus according to Embodiment 10 of the present invention. FIG. 12 is a side view of a conventional exhaust gas purification device.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

(Embodiment 1)
FIG. 1 is a side view of an exhaust gas purification apparatus according to Embodiment 1 of the present invention. First, the configuration of the exhaust gas purification apparatus 1 of Embodiment 1 will be described.

The exhaust gas purification device 1 is connected to a diesel engine 2. The exhaust gas purification device 1 includes a diesel particulate filter 5, an electric heater 6 for regeneration, a blower 8, and an exhaust passage 3. Here, the diesel particulate filter 5 collects the particulates 4 in the exhaust gas. The regeneration electric heater 6 burns and removes the particulate 4 collected by the diesel particulate filter 5.

The exhaust gas purification device 1 may be arranged according to the layout in the engine room of the vehicle. However, it is advantageous for the particulates 4 to be burned and removed when the exhaust gas having the highest exhaust gas temperature flows into the exhaust gas purification device 1. Therefore, the shorter the distance between the exhaust gas purification device 1 and the diesel engine 2, the better.

It is desirable that the diesel particulate filter 5 and the regeneration electric heater 6 are arranged close to each other, and the distance between them is preferably about 10 mm to 20 mm.

In consideration of the durability to the corrosive gas contained in the exhaust gas of the diesel engine 2 and the particulate 4, the regeneration electric heater 6 is a sheathed heater in which a heating element is coated with metal, or a ceramic heater in which ceramic is coated. Etc. are desirable. Examples of the heating element include iron chrome aluminum, nickel chrome, platinum, molybdenum, tantalum, tungsten, silicon carbide, molybdenum silicite, and carbon. Examples of the coating material include stainless steel (SUS304, SUS316L, SUS321, Incoloy 800, Incoloy 825, Inconel 600), aluminum oxide, silicon nitride, and the like in consideration of high temperature durability, corrosion resistance, vibration resistance, and the like. Can be mentioned. The shape of the regeneration electric heater 6 includes a U shape, an M shape, a spiral shape, and the like, but is not particularly limited as long as the shape can be reduced.

The opening / closing part 7 has a check valve structure that is closed when the diesel engine 2 is operated and opened when the diesel engine 2 is stopped. Since the check valve structure can realize complete shut-off and ventilation depending on the ventilation direction, no opening / closing power is required. The pressure for opening and closing the check valve (hereinafter referred to as cracking pressure) is preferably about 20 Pa to 200 Pa. If it falls below this range, complete shutoff is difficult when the diesel engine 2 is operating, and if it exceeds this range, ventilation becomes difficult when the diesel engine 2 is stopped, and the blower 8 becomes large.

The check valve structure is a simple structure, can reliably have an opening / closing function, and the opening / closing part 7 can be downsized. Generally, the opening / closing part 7 includes a gate valve (gate valve), globe valve (ball valve), ball valve, butterfly valve (butterfly valve), needle valve, stop valve, and check valve (check valve, check valve). Valve, check valve). Except for the check valve, opening / closing power is required, and the structure of the opening / closing part 7 is enlarged. If the check valve has a check valve structure, the opening / closing part 7 can be completely shut off and ventilated depending on the direction of ventilation. As the check valve material, stainless steel or the like may be used.

The air blower 8 has a structure that can be attached to the opening / closing part 7 in the middle of the exhaust passage 3 only when the diesel engine 2 is stopped. A simple one-touch coupler or the like may be used to attach and detach the opening / closing unit 7 and the air blowing unit 8. The air blowing unit 8 only needs to output a pressure loss when the particulates 4 are deposited on the diesel particulate filter 5 and a static pressure that can overcome the cracking pressure of the opening / closing unit 7.

Generally, the type of the air blowing unit 8 includes a fan having a compression ratio of 1.1 or less, a blower having a compression ratio of 1.1 or more, and a pump. Examples of the fan include those having a low static pressure, an axial blower (propeller fan), a cross flow blower (cross flow fan), a mixed flow blower (diagonal flow fan), and a centrifugal blower (sirocco fan, turbo fan). . Examples of the blower include a turbo blower and a volume blower. Examples of the pump include non-displacement pumps (centrifugal pumps, propeller pumps, viscous pumps), positive displacement pumps (reciprocating pumps, rotary pumps), injection pumps, bubble pumps, water tank pumps, and submersible pumps.

The electric heater 6 for regeneration and the air blower 8 are driven by an external power source. An oxidation catalyst 14 is carried on the porous wall surface and inside of the diesel particulate filter 5.

The material of the diesel particulate filter 5 is preferably any one of silicon carbide, silicon nitride, and aluminum titanate. Since these are materials having a high melting point, the diesel particulate filter 5 is not melted by the combustion heat of the particulates 4. Moreover, these can increase the amount of the particulates 4 stored in the diesel particulate filter 5 per unit volume, and the diesel particulate filter 5 is reduced in size. Since these are materials having a high heat capacity, the diesel particulate filter 5 heated by high-temperature exhaust gas and the combustion heat of the particulate 4 is difficult to cool, and the temperature at which the oxidation catalyst 14 is activated is maintained for a long time. .

The oxidation catalyst 14 may include one or more metals selected from potassium, vanadium, iron, cobalt, nickel, copper, rubidium, zirconium, niobium, molybdenum, silver, cesium, lanthanum, cerium, and praseodymium. . The oxidation catalyst 14 can efficiently burn the particulate 4 using oxygen in the regenerated air when the engine is stopped. Therefore, the load per unit volume of the diesel particulate filter 5 is increased, and the diesel particulate filter 5 is reduced in size.

Alkali metal potassium, rubidium, and cesium oxides have strong ionic bonding and show reducibility, have low electronegativity, and easily give outermost electrons. Therefore, active oxygen is easily generated, and the particulate 4 is oxidized and burned efficiently.

Among the transition metal vanadium, iron, cobalt, nickel, copper, zirconium, niobium, molybdenum, silver oxides, and lanthanoids with atomic numbers 57 to 71, lanthanum, cerium, and praseodymium oxides have various oxidation states. Take. In addition, since these form non-stoichiometric oxides, active oxygen is easily generated, and the particulates 4 are oxidized and burned efficiently.

The oxidation catalyst 14 is preferably supported on a porous inorganic oxide. As the inorganic oxide, one or more of silica, aluminum oxide, titania, zirconia, zeolite, and magnesia, or two or more composite oxides may be used.

These porous inorganic oxides have a very large surface area. By supporting the oxidation catalyst 14 on these porous inorganic oxides, the catalyst surface area is further increased. Since the contact probability between the particulate 4 and the catalyst surface is improved, and low temperature and highly efficient combustion is possible, the diesel particulate filter 5 is downsized.

Silica varies depending on the type of starting material and the firing temperature during production, but generally has a surface area of about 40 m ² / g or more per unit weight, and is suitable as an inorganic oxide for supporting the oxidation catalyst 14. Yes. Here, the surface area is a so-called specific surface area and is a value determined by the BET method.

Aluminum oxide has a surface area that varies depending on the crystal phase, and α-alumina (corundum type) is generally as small as about 10 m ² / g, which is not preferable as an inorganic oxide for supporting the oxidation catalyst 14. γ-alumina (spinel type) generally varies depending on the type of starting material and the firing temperature during production, but generally has a surface area of 100 m ² / g or more and is suitable as an inorganic oxide for supporting the oxidation catalyst 14. ing.

In general, many titanias have a surface area of about 40 m ² / g or more, and are suitable as inorganic oxides supporting the oxidation catalyst 14. Crystal phases include anatase type (also referred to as anatase type), rutile type, brookite type, and amorphous, and anatase type and rutile type are applicable in consideration of crystal stability in a high temperature atmosphere.

Although zirconia varies depending on the type of starting material and the production method, it generally has a surface area of about 40 m ² / g or more, and is suitable as an inorganic oxide for supporting the oxidation catalyst 14.

Zeolite includes Y-type, mordenite, beta, ZSM-5, etc. depending on the crystal structure, and generally has a surface area of about 300 m ² / g or more, and is suitable as an inorganic oxide for supporting the oxidation catalyst 14.

Magnesia differs depending on the type of starting material and the production method, but generally has a surface area of about 40 m ² / g or more, and is suitable as an inorganic oxide for supporting the oxidation catalyst 14.

Any porous inorganic oxide has a large surface area and is suitable for supporting the oxidation catalyst 14. From the viewpoint of the surface area, γ-alumina (spinel type) and zeolite are preferred. However, the type of metal used is selected depending on the interaction with the oxidation catalyst 14 and the crystal stability.

Next, the operation of the exhaust gas purifying apparatus according to Embodiment 1 of the present invention will be described.

When the diesel engine 2 is operated, the opening / closing part 7 of the check valve structure is automatically shut off, and the air blowing part 8 is removed. Then, the exhaust gas containing the particulates 4 is passed through the diesel particulate filter 5.

The particulate 4 is moved and collected by the Brownian motion on the porous wall surface and the inner surface of the diesel particulate filter 5. Further, the particulates 4 coming later are collected by the deposited layer of the particulates 4 collected.

The particulates 4 collected by the diesel particulate filter 5 are removed by combustion if the exhaust gas temperature reaches the activation temperature of the oxidation catalyst 14, and are deposited without being removed by combustion if the exhaust gas temperature is lower than the activation temperature. move on.

When the diesel engine 2 is stopped, the air blowing unit 8 is connected to the opening / closing unit 7. The regeneration air heated by the regeneration electric heater 6 is blown to the diesel particulate filter 5 by the blower 8. The opening / closing part 7 is opened by the blowing pressure at this time. The blown air is heated by the regeneration electric heater 6, and the particulates 4 accumulated without being removed by combustion during the operation of the diesel engine 2 are removed by combustion to regenerate the diesel particulate filter 5.

When the regeneration of the diesel particulate filter 5 is completed, the air blowing unit 8 is removed from the opening / closing unit 7 and the opening / closing unit 7 is closed.

By repeating this operation, it is possible to prevent the particulate 4 from being excessively deposited on the diesel particulate filter 5. As a result, a decrease in output of the diesel engine 2 caused by an increase in pressure loss of the diesel particulate filter 5 is avoided.

Next, effects of the exhaust gas purifying apparatus according to Embodiment 1 of the present invention will be described.

The air blower 8 is detachable from the opening / closing part 7, and the air blowing part 8 is connected to the opening / closing part 7 only when the diesel engine 2 is stopped. As a result, the entire exhaust gas purification device 1 during operation of the diesel engine 2 is reduced in size.

In addition, by supporting the oxidation catalyst 14 on the diesel particulate filter 5, the particulate 4 is burned at a low temperature and with high efficiency. Therefore, the diesel particulate filter 5 and the regeneration heater 6 are downsized. The material used for the exhaust passage 3 may be a material having low heat resistance.

When the oxidation catalyst 14 is not supported on the diesel particulate filter 5 as in the prior art, it is necessary to raise the temperature to about 600 ° C. to 650 ° C., which is the flammable temperature of the particulate 4. Therefore, a heat insulating structure for keeping the diesel particulate filter 5 warm is required, and the regeneration electric heater 6 is enlarged. Therefore, it is very effective that the oxidation catalyst 14 is supported on the diesel particulate filter 5.

In particular, in order to burn and remove the particulates 4 accumulated when the diesel engine 2 is stopped, the oxidation catalyst 14 that burns the particulates 4 using oxygen in the air is effective. On the other hand, the noble metal catalyst burns the particulate 4 using NOx in the exhaust gas. Since the regeneration air when the diesel engine 2 is stopped does not contain NOx, the combustion efficiency is poor.

Further, the forced regeneration method for forcibly removing and regenerating the particulate 4 accumulated during the operation of the diesel engine 2 requires a fuel pump for injecting fuel when the particulate 4 is combusted. However, the exhaust gas purification apparatus 1 according to Embodiment 1 of the present invention is a batch regeneration system in which the accumulated particulates 4 are removed by combustion and regenerated when the diesel engine 2 is stopped. Therefore, a fuel pump is not necessary, and the entire exhaust gas purification device 1 is reduced in size.

Further, in the case of the forced regeneration system, an oxidation catalyst 14 for burning the injected fuel and raising the exhaust gas temperature is required in front of the diesel particulate filter 5. However, since the exhaust gas purifying apparatus according to Embodiment 1 of the present invention does not require the oxidation catalyst 14, the entire exhaust gas purifying apparatus 1 is downsized.

In addition, when supplying electric power to the regeneration electric heater 6, when supplying electric power from a battery mounted on the diesel engine 2, the battery capacity must be increased by the amount corresponding to the regeneration electric heater 6. However, the electric battery 6 for reproduction is driven by an external power source, so that the mounted battery is reduced in size.

Further, by arranging the regeneration electric heater 6 and the diesel particulate filter 5 close to each other, the entire exhaust gas purification device 1 can be downsized.

Also, the regenerative air is efficiently heated by disposing the regenerative electric heater 6 close to the diesel particulate filter 5. The diesel particulate filter 5 is efficiently heated by feeding the regeneration air into the diesel particulate filter 5 before the heated regeneration air is cooled. Therefore, the regeneration electric heater 6 is reduced in size by the amount of efficiency, and the entire exhaust gas purification device 1 is reduced in size.

(Embodiment 2)
FIG. 2 is a perspective view of the regeneration electric heater of the exhaust gas purifying apparatus according to the second embodiment of the present invention. In the second embodiment of the present invention, the same components as those in the first embodiment are denoted by the same reference numerals, detailed description thereof will be omitted, and different points will be described.

First, the configuration of the regeneration electric heater 6 of the exhaust gas purification apparatus 1 of the second embodiment will be described. The regeneration electric heater 6 includes a metal honeycomb 9 and a band heater 10. The metal honeycomb 9 and the band heater 10 are completely in close contact with each other and stored in the exhaust passage 3.

The metal honeycomb 9 is not particularly limited in structure as long as the same rectifying effect can be obtained with a general honeycomb cell structure (polygon more than a triangle) and a foam structure. The metal honeycomb 9 may be stainless steel considering high temperature corrosion resistance and vibration resistance.

As the band heater 10, it is preferable to take an insulating structure with magnesia powder having higher heat resistance and thermal efficiency than mica. Furthermore, the material used for the band heater 10 is suitably stainless steel.

Next, the operation and effect of the regeneration electric heater 6 of the exhaust gas purification apparatus 1 of Embodiment 2 will be described. In Embodiment 2, a metal honeycomb 9 is used for the electric heater 6 for regeneration. Therefore, when the exhaust gas during operation of the diesel engine 2 and the regenerated air when the diesel engine 2 is stopped pass through the metal honeycomb 9, an effect of rectifying while suppressing the ventilation resistance is obtained. As a result, there is no need to separately provide a rectifying plate in the exhaust gas purification device 1, and the entire exhaust gas purification device 1 is reduced in size.

Also, when the diesel engine 2 is stopped, the regeneration air passing through the metal honeycomb 9 is heated by energizing the band heater 10. At that time, the regenerated air uniformly flows into the diesel particulate filter 5 and the combustibility of the particulate 4 is improved. As a result, the diesel particulate filter 5 is reduced in size, and the entire exhaust gas purification device 1 is reduced in size.

Further, with the configuration of the exhaust gas purification device 1 of the second embodiment, the band heater 10 and the exhaust gas during operation of the diesel engine 2 are not in direct contact. Therefore, the progress of the corrosion caused by the corrosive gas contained in the exhaust gas is suppressed on the surface of the coating material of the band heater 10, and the heater deterioration due to dielectric breakdown is prevented.

Note that an oxidation catalyst 14 for purifying carbon monoxide, hydrocarbons, and the like, which are harmful gas components contained in exhaust gas when the diesel engine 2 is operated, may be supported on the surface of the metal honeycomb 9.

(Embodiment 3)
FIG. 3 is a side view of the exhaust gas purification apparatus according to Embodiment 3 of the present invention. In the third embodiment of the present invention, the same components as those in the first embodiment are denoted by the same reference numerals, detailed description thereof will be omitted, and different points will be described.

In the exhaust gas purification apparatus 1 according to Embodiment 3 of the present invention, the diesel particulate filter 5 and the regeneration electric heater 6 are arranged in the same pipe 11. The diesel particulate filter 5 and the regeneration electric heater 6 are accommodated from both sides of the pipe 11.

Next, the operation and effect of the exhaust gas purification apparatus of Embodiment 3 will be described. Although not shown in the figure, in consideration of maintenance, the diesel particulate filter 5 and the regeneration electric heater 6 are usually housed in separate pipes and connected to each other by a flange. The flange portion has a larger diameter than the piping that houses the diesel particulate filter 5 and the regeneration electric heater 6. Therefore, when the flange portion is thermally insulated, the flange portion is inevitably increased in size by the thickness of the heat insulating material. When the flange portion is not thermally insulated, heat dissipation is promoted from the flange portion, and thus the regeneration electric heater 6 needs to be enlarged by the amount of heat dissipation.

On the other hand, the flange between the diesel particulate filter 5 and the regeneration electric heater 6 can be eliminated by adopting the structure of the exhaust gas purification device 1 of the third embodiment. Therefore, the heat radiation area in the flange portion is reduced, and the heat insulation property is improved. The heat insulation structure 12 is simplified, and the entire exhaust gas purification device 1 is downsized.

It should be noted that by insulating the diesel particulate filter 5 and the regeneration electric heater 6, the following occurs. The exhaust gas temperature can be sent to the diesel particulate filter 5 while the exhaust gas temperature is maintained at a high level when the diesel engine 2 is operating, and the regeneration air temperature is maintained at a high level when the diesel engine 2 is stopped. Therefore, the combustion efficiency of the particulates 4 is increased, and a heat insulating structure is essential for any of the exhaust gas purification apparatuses 1 of the first to third embodiments. As the heat insulating material, a material obtained by melting raw materials such as silica alumina, silica, and aluminum oxide and fiberizing it with high-speed compressed air or centrifugal force is suitable.

(Embodiment 4)
FIG. 4 is a side view of the exhaust gas purification apparatus according to Embodiment 4 of the present invention. In the fourth embodiment of the present invention, the same components as those in the first embodiment are denoted by the same reference numerals, detailed description thereof will be omitted, and different points will be described.

In the exhaust gas purification device 1 according to Embodiment 4 of the present invention, a honeycomb filter 13 is installed on the downstream side of the diesel particulate filter 5. In the following embodiments of the present invention, the upstream side and the downstream side mean a side closer to and far from the air blowing unit 8 in the flow of regenerated air produced by the air blowing unit 8. Therefore, the downstream side of the diesel particulate filter 5 is the direction of the honeycomb filter 13. The honeycomb filter 13 carries platinum or palladium serving as an oxidation catalyst 14 and a porous inorganic oxide serving as a catalyst carrier on a channel wall surface of a metal honeycomb serving as a base material.

Next, the operation and effect of the exhaust gas purification apparatus 1 of Embodiment 4 will be described. When the particulates 4 deposited on the diesel particulate filter 5 are combusted, they are completely combusted into water and carbon dioxide when the amount of deposition is small. However, when the amount of deposition is large, harmful gas is generated without complete combustion. The harmful gases include hydrocarbons and carbon monoxide. The harmful gas is burned and removed by the honeycomb filter 13.

The oxidation catalyst 14 used for the honeycomb filter 13 may contain one or more of platinum and palladium. The harmful gases hydrocarbons and carbon monoxide are most efficiently burned by platinum and palladium. Therefore, the amount of harmful gas combustion per unit volume can be increased. The honeycomb filter 13 is downsized and can be installed in the outlet pipe of the exhaust gas purification device 1 as shown in FIG.

Therefore, even if the honeycomb filter 13 is provided, the overall size of the exhaust gas purification device 1 does not change, and harmful gases are burned and removed while maintaining a reduction in size.

In addition, platinum has high combustion activity of paraffin hydrocarbons (saturated chain compounds) having 3 or more carbon atoms. Palladium has a high combustion activity such as olefinic hydrocarbon (saturated chain compound having a double bond) or methane. Therefore, platinum and palladium may be used in combination. By alloying platinum and palladium, the affinity of the catalyst carrier with the inorganic oxide is increased, and the effect of suppressing sintering of the noble metal particles can be enhanced.

The catalyst carrier used for the honeycomb filter 13 may include a porous inorganic oxide, that is, one or more of aluminum oxide, zirconia, zeolite, and ceria, or two or more composite oxides. By supporting platinum or palladium on the porous inorganic oxide, the surface area of the catalyst is increased, and the contact probability between the harmful gas and the catalyst surface is improved. Since the combustion can be performed at low temperature and high efficiency, the honeycomb filter 13 is downsized.

Also, the porous inorganic oxide adsorbs the harmful gas in the regeneration air and concentrates the harmful gas component in the vicinity of platinum or palladium, so that the contact probability between the harmful gas and the catalyst surface is improved. Therefore, combustion at a low temperature and high efficiency becomes possible, and the honeycomb filter 13 is downsized.

The base material used for the honeycomb filter 13 is preferably a metal honeycomb. Metal honeycombs have a lower heat capacity than commonly used cordierite honeycombs. However, the metal honeycomb has a high thermal conductivity, and the heat of the low energy regenerated air after passing through the diesel particulate filter 5 can be efficiently transmitted to the oxidation catalyst 14 carried on the honeycomb filter 13. Therefore, the amount of harmful gas combustion per unit volume can be increased, and the honeycomb filter 13 can be downsized.

Moreover, the metal honeycomb can be installed by being welded to the inner wall of the exhaust passage 3. Therefore, the diameter of the exhaust passage 3 can be reduced, and the exhaust gas purification device 1 is downsized. Since the cordierite honeycomb is fixed in the exhaust passage 3 using an inorganic expansion mat or the like, it is necessary to increase the diameter of the exhaust passage 3 by an amount corresponding to the expansion mat, and the exhaust gas purification device 1 is increased in size. .

The installation position of the honeycomb filter 13 is preferably as close as possible to the diesel particulate filter 5. When the regeneration air is allowed to flow into the honeycomb filter 13 while keeping the temperature of the regeneration air high, the harmful gas is burned more efficiently.

As described above, in the honeycomb filter 13, platinum or palladium serving as the oxidation catalyst 14 and a porous inorganic oxide serving as a catalyst carrier are supported on the channel wall surface of the metal honeycomb. By installing the honeycomb filter 13 on the downstream side of the diesel particulate filter 5 and in the outlet pipe of the exhaust gas purification device 1, the overall size of the exhaust gas purification device 1 does not change, and it is harmful while maintaining a reduction in size. The gas is burned off. Furthermore, since the honeycomb filter 13 can be reduced in size as described above, an increase in pressure loss due to the installation of the honeycomb filter 13 can be suppressed, and an increase in the size of the blower unit 8 can also be suppressed.

(Embodiment 5)
FIG. 5 is a side view of an exhaust gas purification apparatus according to Embodiment 5 of the present invention, and FIG. 6 is a configuration diagram showing a control unit of the exhaust gas purification apparatus. In the fifth embodiment of the present invention, the description of the same configuration and effect as those of the first embodiment will be omitted, and only different points will be described.

As shown in FIG. 5, the exhaust gas purification device 51 is connected to a diesel engine 52. The exhaust gas purification device 51 includes a filter unit 54 that houses a diesel particulate filter 56 and an electric heater 57 for regeneration, a blower unit 59, an exhaust passage 53, and a control unit 60. The exhaust passage 53 has an upstream side exhaust passage 53 a upstream from the filter portion 54 and a downstream side exhaust passage 53 b downstream from the filter portion 54. Here, the diesel particulate filter 56 is disposed between the upstream side exhaust passage 53a and the downstream side exhaust passage 53b, and collects the particulates 55 in the exhaust gas. The regeneration electric heater 57 burns and removes the particulate 55 collected by the diesel particulate filter 56.

As shown in FIG. 6, the control unit 60 instructs the regeneration electric heater 57 and the air blowing unit 59 to operate and stop. The control unit 60 supplies power to the regeneration electric heater 57 and the air blowing unit 59 using an external power source as a driving power source. The control unit 60 is connected to the detection unit 61 of the exhaust gas purification device 51.

Examples of the detector 61 include a transformer, a heater temperature detector, an in-filter temperature detector, a pressure detector, and a CO ₂ concentration detector. Here, the transformer changes the output of the regeneration electric heater 57 to an arbitrary output value. The heater temperature detection unit detects the heater temperature of the regeneration electric heater 57. The filter internal temperature detection unit detects the internal temperature of the diesel particulate filter 56. A pressure detection part detects the pressure in the pipe line between the ventilation part 59 and the upstream exhaust passage 53a. CO ₂ concentration detector detects the concentration of CO ₂ in the regeneration air downstream of the diesel particulate filter 56. In order to reduce the size of the exhaust gas purification device 51, each detection means should be as small as possible.

In addition, as the transformer, there is one in which the output value from the transformer is controlled by a multi-step adjustment (step control) switch, a select switch, a toggle switch, and the like. However, the transformer may have any function that can control the output of the regeneration electric heater 57.

The heater temperature detector and filter internal temperature detector include thermocouples, platinum resistance thermometers, thermistors, radiation thermometers, and expansion thermometers. However, there is a function that can detect the heater temperature and the filter internal temperature. That's fine.

Further, as the pressure detection unit, there are a Prudon type, a semiconductor strain gauge type, a capacitance type, a semiconductor piezoresistive type, a silicon resonant type, etc., as long as it has a function capable of detecting the pressure in the pipeline.

As the CO ₂ concentration detection unit, there are a solid electrolyte system, a non-dispersion type infrared absorption system, and the like, but any CO ₂ concentration detection unit may be used as long as it has a function of detecting the CO ₂ concentration in the regeneration air.

The control unit 60 also includes a timer 73. As the timer 73, there are a method of counting down a remaining time until a preset time, a method of counting up an elapsed time from the start of reproduction, and the like. However, the timer 73 may have any function that can stop the regeneration operation at the set time or time.

Next, the operation and action of the exhaust gas purification device 51 of the fifth embodiment will be described.

During the operation of the diesel engine 52, the opening / closing part 58 of the check valve structure is automatically shut off, and the exhaust gas containing the particulate 55 is passed through the diesel particulate filter 56 through the exhaust gas purification device 51.

The particulate 55 is moved and collected on the porous wall surface and the inner surface of the diesel particulate filter 56 by Brownian motion. Further, the particulates 55 coming later are collected by the deposited layer of the particulates 55 collected.

The particulates 55 collected by the diesel particulate filter 56 are removed by combustion if the exhaust gas temperature reaches the combustion temperature of the particulates 55, and if the temperature is lower than the combustion temperature, deposition proceeds without being removed by combustion.

When the diesel engine 52 is stopped, the blowing unit 59 is connected to the opening / closing unit 58, and the blowing unit 59 is driven by the control unit 60 to blow external air to the diesel particulate filter 56 as regenerated air. The opening / closing unit 58 is opened by the blowing pressure, and the regeneration air is heated by the regeneration electric heater 57 operated based on the output from the control unit 60. Then, the particulate 55 accumulated without being burned and removed during operation of the diesel engine 52 is burned and removed, and the diesel particulate filter 56 is regenerated. The regeneration of the diesel particulate filter 56 can be performed while the detection unit 61 is connected to the control unit 60 and controlled based on the signal from the detection unit 61.

When regeneration of the diesel particulate filter 56 is completed, the electric heater 57 for regeneration and the air blowing unit 59 are stopped, and then the air blowing unit 59 is removed from the opening / closing unit 58 and the opening / closing unit 58 is closed.

By repeating this operation, the particulate 55 is prevented from being excessively deposited on the diesel particulate filter 56. As a result, a decrease in output of the diesel engine 52 caused by an increase in pressure loss of the diesel particulate filter 56 is avoided.

Next, the effect of the exhaust gas purification device 51 of the fifth embodiment will be described.

The air blower 59 is detachable from the opening / closing part 58. Only when the diesel engine 52 is stopped, the blower unit 59 is connected to the opening / closing unit 58, whereby the entire exhaust gas purifying device 51 during operation of the diesel engine 52 is downsized. That is, when the exhaust gas purification device 51 is installed in the engine room, if the exhaust gas purification device 51 as a whole is miniaturized during operation of the diesel engine, the engine room is also miniaturized and the visibility of the driver is improved. The

Also, by supporting the oxidation catalyst on the diesel particulate filter 56, the particulate 55 can be combusted at low temperature and high efficiency. Therefore, the diesel particulate filter 56 and the regeneration electric heater 57 are reduced in size, and the power consumption during regeneration is reduced.

Further, when the control unit 60 is connected to a transformer for changing the output of the regeneration heater 57 to an arbitrary output value, it can be changed to an optimum output value according to the outside air temperature. As a result, the regeneration efficiency of the diesel particulate filter 56 is not lowered, and the power consumption during regeneration can be reduced.

Further, the control unit 60 is connected to a heater temperature detection unit that detects the heater temperature of the electric heater 57 for regeneration. Therefore, the temperature of the diesel particulate filter 56 at the time of regeneration is maintained at an appropriate temperature without being too high or too low. As a result, the particulate 55 is burned efficiently and reliably, and the power consumption during regeneration is reduced.

Further, the control unit 60 is connected to a filter internal temperature detection unit that detects the internal temperature of the diesel particulate filter 56. Therefore, the internal temperature of the diesel particulate filter 56 is detected, and the temperature of the diesel particulate filter 56 at the time of regeneration is maintained at an appropriate temperature without being too high or too low. As a result, the particulate 55 is burned efficiently and reliably, and the power consumption during regeneration is reduced.

Further, the control unit is connected to a pressure measurement unit that detects the pressure in the pipe line between the air blowing unit 59 and the upstream side exhaust passage 53a. When the diesel particulate filter 56 is regenerated, if the regenerative electric heater 57 is energized in a state where the regenerative air is not flowing, it will be in an unsafe state such as a decrease in electrical insulation or burning due to overheating. Therefore, when the regeneration air is not flowing in the exhaust passage 53, that is, when the pressure in the exhaust passage 53 is not more than a specified value, the output to the regeneration electric heater 57 is cut off by the interlock, and the diesel engine The curate filter 56 is safely regenerated.

Further, the control unit 60 is connected downstream of the diesel particulate filter 56 to a CO ₂ concentration detection unit that can detect the CO ₂ concentration in the regeneration air. It is determined that regeneration of the diesel particulate filter 56 has been completed when the CO ₂ concentration has decreased to the same level as the regeneration air before the start of regeneration, that is, when the particulate 55 deposited on the diesel particulate filter 56 has finished burning. Is done. By determining that the time is the time when the output to the regeneration electric heater 57 is cut off, the regeneration time of the diesel particulate filter 56 is not excessive and insufficient, and the power consumption during regeneration is reduced.

Also, the control unit 60 has a timer 73. Since the output of the regeneration electric heater 57 and the blower 59 is cut off at a preset time, the regeneration of the diesel particulate filter 56 at night can be performed unattended, and the power consumption during regeneration is reduced.

(Embodiment 6)
FIG. 7 is a side view of the exhaust gas purifying apparatus according to Embodiment 6 of the present invention. In the sixth embodiment of the present invention, the same components as those of the fifth embodiment are denoted by the same reference numerals, detailed description thereof will be omitted, and different points will be described.

First, the configuration of the exhaust gas purifying device 80 of the sixth embodiment will be described. The exhaust gas purification device 80 of the sixth embodiment is further provided with a bypass opening / closing part 64 and a bypass pipe 63 with respect to the exhaust gas purification device 51 of the fifth embodiment. Here, the bypass opening / closing part 64 is provided in the downstream side exhaust passage 53b. The bypass pipe 63 communicates the bypass opening / closing part 64 and the outside air inlet 62 provided in the air blowing part 59 on the upstream side of the air blowing part 59. The blower 59 mixes the circulated regenerated air in which part of the regenerated air that has passed through the filter unit 54 is attracted and the external air sucked from the outside air intake 62, and blows the air to the upstream exhaust passage 53a.

Next, the operation and action of the exhaust gas purification device 80 of the sixth embodiment will be described. When the diesel engine 52 is stopped, the blower 59 is connected to the opening / closing part 58, the bypass pipe 63 is connected to the bypass opening / closing part 64, and the blower 59 and the regeneration electric heater 57 are operated by the controller 60.

The opening / closing unit 58 is opened by the blowing pressure generated by the blowing from the blowing unit 59, and the bypass opening / closing unit 64 is opened manually or by a signal from the control unit 60. The outside air inlet 62 and the bypass pipe 63 are connected on the upstream side of the air blowing unit 59 and further connected to the air blowing unit 59. When the air blower 59 is operated, the air blower 59 mixes the circulated regenerated air and the external air from the outside air intake 62 and blows the regenerated air to the upstream side exhaust passage 53a. The bypass pipe 63 has a long pressure line with respect to the outside air inlet 62 and has a large pressure loss due to bending and the like. Due to this pressure loss difference, the blower 59 mainly takes in external air and blows it to the upstream exhaust passage 53a.

Next, the effect of the exhaust gas purification device 80 of the sixth embodiment will be described. When the diesel particulate filter 56 is regenerated, part of the regenerated air that has once passed through the filter unit 54 and heated by the regenerating electric heater 57 is not exhausted outside the exhaust gas purification device 80 as it is. A part of the regeneration air heated by the regeneration electric heater 57 and the external air are mixed and reused as regeneration air. As a result, the temperature of the regeneration air blown to the upstream side exhaust passage 53a can be raised, so that the output value of the regeneration heater 57 can be lowered, and the power consumption during regeneration is reduced.

(Embodiment 7)
FIG. 8 is a side view of the exhaust gas purification apparatus according to Embodiment 7 of the present invention. In the seventh embodiment of the present invention, the same components as those of the fifth embodiment are denoted by the same reference numerals, detailed description thereof will be omitted, and different points will be described.

First, the configuration of the exhaust gas purification device 81 of the seventh embodiment will be described. The exhaust gas purification device 81 of the seventh embodiment further includes a bypass switching unit 65, a bypass pipe connection unit 66, a bypass pipe 67, and an air release unit 68 with respect to the exhaust gas purification device 51 of the fifth embodiment. I have. Here, the bypass switching unit 65 is provided in the downstream side exhaust passage 53b. The bypass pipe connecting portion 66 is connected to the downstream side exhaust passage 53b in the bypass switching portion 65. The bypass pipe 67 communicates the bypass pipe connecting portion 66 and the air blowing portion 59. The air release portion 68 is disposed in the middle of the bypass pipe 67 in order to release the pressure in the bypass pipe 67. The blowing unit 59 blows the regenerated air that has passed through the filter unit 54 to the upstream side exhaust passage 53a using the regenerated air that returns to the blowing unit 59 through the bypass pipe 67 or the external air as the regenerated air.

Next, the operation and action of the exhaust gas purification device 81 of the seventh embodiment will be described. When the diesel engine 52 is stopped, the air blowing part 59 is connected to the opening / closing part 58 and the bypass pipe 67 is connected to the bypass pipe connection part 66. The bypass switching unit 65 switches the flow path of the exhaust gas from the flow path that exhausts out of the exhaust gas purification device 81 from the filter section 54 to the flow path from the filter section 54 to the bypass pipe 67. The flow path switching by the bypass switching unit 65 may be either manual or automatic by the control unit 60.

The blower unit 59 and the regeneration electric heater 57 are operated by the control unit 60. The regeneration air blown from the blower 59 to the upstream exhaust passage 53 a is heated by the regeneration electric heater 57. The regeneration air passes through the diesel particulate filter 56 and burns and removes the particulate 55. Then, the regeneration air flows from the downstream side exhaust passage 53 b to the bypass pipe 67 by the bypass switching unit 65 and returns to the blowing unit 59. The air blower 59 uses the air from the bypass pipe 67 as circulation regenerated air and blows the air again to the filter part 54 through the upstream exhaust passage 53a.

The air release portion 68 disposed in the middle of the bypass pipe 67 has a structure for releasing the pressure in the circulation path to the outside when the pressure of the circulation path of the regeneration air becomes high. Here, the circulation path of the regeneration air includes a blower 59, an upstream exhaust passage 53a, a filter portion 54, a downstream exhaust passage 53b, and a bypass pipe 67.

Next, the effect of the exhaust gas purification device 81 of the seventh embodiment will be described. At the time of regeneration of the diesel particulate filter 56, part of the regenerated air that has once passed through the filter unit 54 and heated by the regeneration electric heater 57 is not exhausted outside the exhaust gas purification device 81 as it is. Part of the regeneration air heated by the regeneration electric heater 57 is reused as regeneration air, and the regeneration air having a high temperature is blown into the upstream exhaust passage 53a. Therefore, the output value of the regeneration electric heater 57 is lowered, and the power consumption during regeneration is reduced.

(Embodiment 8)
FIG. 9 is a side view of the exhaust gas purifying apparatus according to the eighth embodiment of the present invention. In the eighth embodiment of the present invention, the same components as those in the fifth embodiment are denoted by the same reference numerals, detailed description thereof will be omitted, and different points will be described.

First, the configuration of the exhaust gas purification device 82 according to the eighth embodiment will be described. The exhaust gas purification device 82 according to the eighth embodiment is different from the exhaust gas purification device 51 according to the fifth embodiment in that a bypass switching unit 65, a bypass pipe connection unit 66, and a blower supply pipe 59a connected to the blower 59 are provided. Further, a bypass heating pipe 69 is further provided. Here, the bypass switching unit 65 is provided in the downstream side exhaust passage 53b. The bypass pipe connecting portion 66 is connected to the downstream exhaust passage 53b at the position where the bypass switching portion 65 is disposed. The bypass heating pipe 69 is connected to the bypass pipe connecting portion 66, and one end is opened to the outside air to exhaust the exhaust gas to the outside. The bypass pipe connection part 66 and the air blowing part air supply pipe 59a communicate with each other.

Next, the operation and action of the exhaust gas purification device 82 according to the eighth embodiment will be described. When the diesel engine 52 is stopped, the blower 59 is connected to the opening / closing part 58, and the bypass heating pipe 69 is connected to the bypass pipe connection part 66. The flow path of the exhaust gas is switched by the bypass switching section 65 from the flow path exhausted from the filter section 54 to the outside of the exhaust gas purification device 82 to the flow path from the filter section 54 to the bypass heating pipe 69. The flow path switching by the bypass switching unit 65 may be either manual or automatic by the control unit 60.

The blower unit 59 and the regeneration electric heater 57 are operated by the control unit 60. The air blowing unit 59 takes in external air and blows it to the filter unit 54 as regenerated air. The regeneration air is heated by the regeneration electric heater 57, passes through the diesel particulate filter 56, and the particulate 55 is burned and removed. Then, the regenerative air passes through the bypass heating pipe 69 disposed so as to cover the air blowing section air supply pipe 59a from the downstream side exhaust passage 53b by the bypass switching section 65 and is exhausted to the outside of the exhaust gas purification device 82.

Next, the effect of the exhaust gas purification device 82 of the eighth embodiment will be described. At the time of regeneration of the diesel particulate filter 56, the regeneration air once passes through the filter unit 54, is heated by the regeneration electric heater 57, and is exhausted outside the exhaust gas purification device 82. At that time, the regenerated air passes through the bypass heating pipe 69 arranged so as to cover the blower air supply pipe 59a. Thus, the air heated by passing through the filter unit 54 preheats the regenerated air newly blown to the filter unit 54. As a result, since the regeneration air is efficiently heated by the regeneration electric heater 57, the output of the regeneration electric heater 57 is reduced, and the power consumption during regeneration is reduced.

(Embodiment 9)
FIG. 10 is a side view of the exhaust gas purifying apparatus according to Embodiment 9 of the present invention. In the ninth embodiment of the present invention, the same components as those of the fifth embodiment are denoted by the same reference numerals, detailed description thereof will be omitted, and different points will be described.

First, the configuration of the exhaust gas purification device 83 of the ninth embodiment will be described. The exhaust gas purification device 83 according to the ninth embodiment further includes a bypass switching unit 65 and an exhaust heating pipe 85 with respect to the exhaust gas purification device 51 according to the fifth embodiment. Here, the bypass switching unit 65 is provided in the downstream side exhaust passage 53b. Pipe line 70 communicates bypass switching unit 65 with exhaust heating pipe 85 disposed so as to cover portions of electric heater 57 for regeneration and diesel particulate filter 56.

Next, the operation and action of the exhaust gas purification device 83 of the ninth embodiment will be described. When the diesel engine 52 is stopped, the blower unit 59 is connected to the opening / closing unit 58, and the flow path of the exhaust gas is bypassed by the bypass switching unit 65 from the flow path exhausted from the filter unit 54 to the outside of the exhaust gas purification device 83. To the exhaust heating pipe 85. The flow path switching by the bypass switching unit 65 may be either manual or automatic by the control unit 60.

The blower unit 59 and the regeneration electric heater 57 are operated by the control unit 60. The air blowing unit 59 takes in external air and blows it to the filter unit 54 as regenerated air. The regeneration air is heated by the regeneration electric heater 57, passes through the diesel particulate filter 56, and burns and removes the particulate 55 deposited on the diesel particulate filter 56. The regeneration air passes through the exhaust heating pipe 85 disposed so as to cover the filter unit 54 from the downstream side exhaust passage 53 b by the bypass switching unit 65 and is exhausted to the outside of the exhaust gas purification device 83.

Next, the effect of the exhaust gas purification device 83 of the ninth embodiment will be described. At the time of regeneration of the diesel particulate filter 56, the regeneration air passes once through the filter unit 54, is heated by the regeneration electric heater 57, and is exhausted outside the exhaust gas purification device 83. At that time, the regenerated air passes through the exhaust heating pipe 85 disposed so as to cover the filter portion 54. As a result, the regenerated air that has been heated by passing through the filter portion 54 passes around the filter portion 54 and is exhausted to the outside of the exhaust gas purification device 83. As a result, the amount of heat released from the inside of the filter unit 54 to the outside is suppressed, and the diesel particulate filter 56 by the regeneration electric heater 57 is efficiently heated, so the output of the regeneration electric heater 57 is reduced, Power consumption during playback is reduced.

Note that a heat insulating structure such as a heat insulating material, an air layer, a vacuum layer, or the like may be provided around the filter portion 54, and the exhaust heating pipe 85 may be disposed so as to cover the heat insulating structure. As a result, the amount of heat released from the filter unit 54 is further reduced, and the power consumption during regeneration is further reduced.

(Embodiment 10)
FIG. 11 is a side view of the exhaust gas purifying apparatus according to Embodiment 10 of the present invention. In the tenth embodiment of the present invention, the same components as those in the fifth embodiment are denoted by the same reference numerals, detailed description thereof will be omitted, and different points will be described.

First, the configuration of the exhaust gas purification device 84 of the tenth embodiment will be described. The exhaust gas purifying device 84 of the tenth embodiment further includes an introduction pipe opening / closing part 72 and a regeneration air introduction pipe 71. The exhaust gas purification device 84 connects the blower 59 and the regenerative air introduction pipe 71 when the diesel particulate filter 56 is regenerated. The introduction pipe opening / closing part 72 communicates the middle of the upstream side exhaust passage 53 a and the regeneration air introduction pipe 71. The regeneration air introduction pipe 71 is disposed so as to cover a portion where the regeneration electric heater 57 is disposed.

Next, the operation and action of the exhaust gas purification device 84 of the tenth embodiment will be described. When the diesel engine 52 is stopped, the blower 59 is connected to the regeneration air introduction pipe 71, and the blower 59 and the regeneration electric heater 57 are operated by the controller 60. The regeneration air blown from the blower 59 passes through the regeneration air introduction pipe 71, the introduction pipe opening / closing part 72, and the upstream exhaust passage 53 a and flows to the filter part 54. The introduction pipe opening / closing part 72 is structured to open by the blowing pressure of the regeneration air.

Next, the effect of the exhaust gas purification device 84 of the ninth embodiment will be described. At the time of regeneration of the diesel particulate filter 56, the regeneration air is blown from the blower 59, and flows into the upstream exhaust passage 53a in contact with the outer periphery of the filter 54 where the regeneration heater 57 is disposed. As a result, the regenerated air is preheated by the heat released from the inside of the filter unit 54 to the outside, so that the output of the regeneration electric heater 57 is reduced and the power consumption during regeneration is reduced.

The present invention is useful not only for automobiles but also for exhaust gas purification devices mounted on construction machines, generators, forklifts, cultivators, ships, and the like.

1, 51, 80, 81, 82, 83, 84 Exhaust gas purification device 2,52 Diesel engine 3,53 Exhaust passage 4,55 Particulate 5,56 Diesel particulate filter 6,57 Regenerative electric heater 7,58 Open / close Portions 8 and 59 Air blower 9 Metal honeycomb 10 Band heater 11 Pipe 12 Heat insulation structure 13 Honeycomb filter 14 Oxidation catalyst 53a Upstream exhaust passage 53b Downstream exhaust passage 54 Filter portion 59a Air blower air supply pipe 60 Control unit 61 Detection unit 62 Outside air Intake 63 Bypass pipe 64 Bypass opening / closing part 65 Bypass switching part 66 Bypass pipe connection part 67 Bypass pipe 68 Atmospheric release part 69 Bypass heating pipe 70 Pipe line 71 Regenerative air introduction pipe 72 Introduction pipe opening / closing part 73 Timer 85 Exhaust heating pipe

Claims (23)

A diesel particulate filter that collects particulates in the exhaust gas in the exhaust passage of the diesel engine;
An electric heater for regeneration that burns and removes the particulates collected by the diesel particulate filter;
In an exhaust gas purifying device comprising a blower unit,
The diesel particulate filter carries an oxidation catalyst,
The diesel particulate filter and the regeneration electric heater driven by an external power source are arranged close to each other,
The air blowing unit is driven by an external power source,
An opening / closing part that makes the air blowing part detachable in the exhaust passage is disposed,
When the diesel engine is operating, remove the air blowing part from the opening and closing part,
An exhaust gas purifying apparatus characterized in that, when the diesel engine is stopped, the blowing section is connected to the opening / closing section, and the regeneration air heated by the regeneration electric heater is blown to the diesel particulate filter by the blowing section. The exhaust gas purification apparatus according to claim 1, wherein the opening / closing portion has a check valve structure. The exhaust gas purifying apparatus according to claim 1, wherein the regeneration electric heater comprises a combination of a metal honeycomb and a band heater. The diesel particulate filter and the regeneration electric heater are disposed in the same pipe, and the diesel particulate filter and the regeneration electric heater are housed from both sides of the pipe, respectively. The exhaust gas purification apparatus as described. The exhaust gas purification apparatus according to claim 1, wherein the oxidation catalyst burns the particulates using oxygen in the regeneration air. The exhaust gas purification device according to claim 1, wherein the oxidation catalyst is supported on a porous inorganic oxide. The exhaust gas purification device according to claim 1, wherein the material of the diesel particulate filter is any one of silicon carbide, silicon nitride, and aluminum titanate. The oxidation catalyst includes at least one metal selected from potassium, vanadium, iron, cobalt, nickel, copper, rubidium, zirconium, niobium, molybdenum, silver, cesium, lanthanum, cerium, and praseodymium. The exhaust gas purification device according to claim 5. The exhaust gas according to claim 6, wherein the inorganic oxide includes one or more of silica, aluminum oxide, titania, zirconia, zeolite, and magnesia, or two or more complex oxides. Gas purification device. The exhaust gas purification apparatus according to claim 1, wherein a honeycomb filter for purifying hydrocarbons or carbon monoxide is disposed downstream of the diesel particulate filter. The exhaust gas purifying device according to claim 10, wherein the honeycomb filter contains one or more of platinum and palladium. The catalyst carrier used for the honeycomb filter is a porous inorganic oxide, and includes any one or more of aluminum oxide, zirconia, zeolite, and ceria, or two or more complex oxides. The exhaust gas purification device according to claim 10. The exhaust gas purification device according to claim 10, wherein a base material of the honeycomb filter is a metal honeycomb. 2. The exhaust gas according to claim 1, wherein the exhaust passage includes an upstream exhaust passage and a downstream exhaust passage, and a control unit for operating the regeneration electric heater and the blower is operated and stopped. Purification equipment. 15. The exhaust gas purifying apparatus according to claim 14, wherein the control unit includes a transformation unit that changes an output of the electric heater for regeneration to an arbitrary output value. The exhaust gas purification apparatus according to claim 14, wherein the control unit is connected to a heater temperature detection unit that detects a heater temperature of the regeneration electric heater. The exhaust gas purification device according to claim 14, wherein the control unit is connected to an in-filter temperature detecting unit that detects an internal temperature of the diesel particulate filter. The exhaust gas purification device according to claim 14, wherein the control unit includes a timer. The exhaust gas purification device according to claim 14, further comprising a bypass opening / closing portion provided in the downstream side exhaust passage, and a bypass pipe communicating the bypass opening / closing portion and the blower portion. A bypass switching part provided in the downstream exhaust passage, a bypass pipe connecting part connected to the bypass switching part, a bypass pipe communicating the bypass pipe connecting part and the blower part, and a middle of the bypass pipe 15. The exhaust gas purifying apparatus according to claim 14, further comprising an atmosphere opening portion arranged to relieve pressure in the bypass pipe. A bypass switching unit provided in the downstream exhaust passage, a bypass pipe connecting unit connected to the bypass switching unit, a blower air supply pipe connected to the blowing unit, the bypass pipe connecting unit, and the blowing unit The exhaust gas purification device according to claim 14, further comprising a bypass heating pipe communicating with the air supply pipe and having one end open to the outside air. A bypass switching unit provided in the downstream exhaust passage, and a conduit communicating with the exhaust switching pipe disposed so as to cover the bypass switching unit and the regeneration electric heater and the diesel particulate filter. The exhaust gas purification device according to claim 14, further comprising: A regenerative air introduction pipe disposed so as to cover a part of the regeneration electric heater; and an introduction pipe opening / closing portion communicating the middle of the upstream exhaust passage and the regenerative air introduction pipe. 15. The exhaust gas purifying apparatus according to claim 14, wherein when the filter is regenerated, the blowing section and the regenerative air introduction pipe are connected.

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