JPH06173643A - Exhaust gas treatment device - Google Patents

Abstract

PURPOSE:To provide an exhaust gas treatment device to incinerate carbon by carrying an electric current in electrically conductive metallic pipes, and heating porous ceramics filters inside of them. CONSTITUTION:Porous ceramics pipe-shaped filters 4 are arranged in electrically conductive metallic pipes 22, and electric power from a generator of a turbo charger is always supplied to the metallic pipes 22, and the filters 4 are heated by the metallic pipes 22, and carbon scavenged by the filters 4 is burnt. A large number of metallic pipes 22 are arranged in an exhaust gas passage 2 in a mutual noncontact condition in a lengthwise direction in an exhaust gas flowing direction, and the end parts are connected to each other by connecting members 15, and the filters 4 are constituted in a continuous heater.

Description

Detailed Description of the Invention

[0001]

This invention relates to an engine, a combustion furnace,
To purify the exhaust gas discharged from incinerators,
The present invention relates to an exhaust gas treatment device having a filter arranged in a case incorporated in an exhaust system.

[0002]

2. Description of the Related Art Combustion of a diesel engine is based on so-called heterogeneous mixing, in which fuel is injected into high temperature, high pressure air. Heterogeneous mixing is different from homogeneous mixture in that air and fuel are not uniformly mixed, so the carbon component in the fuel changes to soot, HC, etc. due to the high temperature heat of combustion, and they aggregate to form particulates, It is released into the air. The smoke becomes particulates in which finely divided carbon and hydrocarbons adhere to the outer periphery thereof and floats in the atmosphere, so that pollution of the urban environment progresses and the transparency of the air deteriorates extremely.

Conventionally, as an exhaust gas treatment device for treating engine exhaust gas, for example, cordierite (2M
An exhaust particulate purifying device for a diesel engine is disclosed in which two sets of filters having a porous honeycomb structure made of gO.2Al ₂ O ₃ .5SiO ₂ ) are arranged in parallel in an exhaust passage. The exhaust gas purification apparatus of the diesel engine passes the exhaust gas through one of the filters having a honeycomb structure, collects carbon in the exhaust gas by the filter, and when the carbon is deposited and clogged in the filter, Cut off exhaust gas flow to the filter, switch to flow exhaust gas to another filter, send air from the downstream side of the clogged filter, heat the filter and incinerate the clogged carbon It is a thing. As an exhaust particulate purifying device for such a diesel engine, for example, there is one disclosed in Japanese Utility Model Laid-Open No. 1-144427.

Further, Japanese Utility Model Laid-Open No. 1-111123 discloses a regeneration device for a diesel exhaust purification filter. The diesel exhaust gas purification filter regeneration device includes a honeycomb filter that collects particulates in exhaust gas, a heater that is arranged on the upstream side of the filter,
And a plug provided with a tapered through hole that communicates the inside and outside of the filter provided near the heater.
A similar device is disclosed in Japanese Utility Model Laid-Open No. 63-22315.

Further, Japanese Utility Model Laid-Open No. 3-116722 discloses an exhaust gas purifying device for a diesel engine. The exhaust gas purifying apparatus for a diesel engine has a columnar ceramic filter in which a large number of cells extending in the longitudinal direction are formed, and an electric heating member provided on the outer periphery of the filter. , Which is filled with powder having good thermal conductivity.

[0006]

The particulates or smoke such as carbon and HC contained in the exhaust gas discharged from the diesel engine are said to have a diameter of about 200Å, but they gradually aggregate. And grows into soot having a diameter of 10 μm to 20 μm. These soots normally burn at a temperature of 600 ° C to 700 ° C if oxygen is present.

However, although many devices for removing smoke have been developed in the past, they all have drawbacks and cannot be put to practical use at present. In a DPF, that is, an exhaust gas treatment device that collects and incinerates particulates (P) such as carbon, soot, and HC contained in exhaust gas exhausted from a diesel engine (D) by a filter (F), the particulates are filtered. When it is collected by the body or the filter and the particulates are deposited on the filter,
It is heated by a glow plug for ignition or a heater to incinerate particulates such as soot.

However, in such a particulate incineration method, the temperature rises excessively due to the combustion of soot and the like, and, for example, a ceramic filter such as cordierite is cracked, cracked, burnt, etc., and the filter is damaged. There is a problem in that it is not preferable in practical use.
In particular, even if the filter is made of heat-resistant ceramics, in the non-uniform combustion of particulates such as soot deposited on the filter, there are many high temperature parts locally in the filter,
In many cases, cracks or the like occur in the ceramics that make up the filter.

Therefore, an object of the present invention is to solve the above-mentioned problems, and it is arranged in a case incorporated in an exhaust system for purifying exhaust gas discharged from an engine, a combustion furnace, an incinerator and the like. In particular, the present invention relates to an exhaust gas treatment device that incinerates particulates such as carbon, soot, and HC in exhaust gas emitted from a diesel engine by using a heat-resistant ceramics and In order to prevent the presence of particulates in the filter from locally depositing and to ensure uniform combustion in the filter, the ceramic filter is surrounded by a metal pipe with gas holes, and the metal pipe is energized. The filter is constantly heated, the flow rate of exhaust gas is reduced when carbon is deposited, and the particulates such as carbon, soot, and HC are incinerated to produce gas. The exhaust gas purifying, yet is to provide an exhaust gas treatment apparatus using the power recovered power to be supplied to the metal pipe by the exhaust gas energy of the engine.

[0010]

In order to achieve the above object, the present invention is configured as follows. That is,
The present invention relates to a conductive and heat-resistant metal pipe in which a large number of gas passage holes are formed in a case incorporated in an exhaust passage in a non-contact state in the longitudinal direction in the flow direction of exhaust gas, and the inside of the metal pipe. , A pipe-shaped filter made of heat-resistant porous ceramics and having closed downstream ends, electrically connecting the ends of the metal pipes in pairs and connecting the metal pipes in series The present invention relates to an exhaust gas treatment device comprising a large number of conductive connecting members and a power supply source that supplies power to the metal pipe to burn particulates collected by the filter.

Further, in this exhaust gas treatment device, the power supply source is composed of a generator that generates power by the operation of a turbocharger driven by the exhaust gas energy of the engine.

Further, in this exhaust gas treatment device, the porous ceramics constituting the filter is Si.
It is a ceramic selected from C, Si ₃ N ₄ , Al ₂ O ₃ , and Al ₂ TiO ₅ , and has a porosity of substantially 50% or more and a through hole diameter of about 20 μm.

Further, in this exhaust gas treatment device, the metal pipe is made of a refractory metal of Ni or Cr type.

Further, in this exhaust gas treatment apparatus, a case incorporated in an exhaust pipe communicating with an exhaust passage downstream of a turbocharger provided in an engine is separated from each other in a longitudinal direction in a non-contact state in a flow direction of the exhaust gas. A large number of pipe-shaped filters placed, a power supply source that supplies power to a metal pipe that heats the filter to incinerate particulates collected by the filter, and a bypass that bypasses the filter branched from the exhaust passage. A passage, an exhaust pipe control valve that opens and closes by an exhaust pipe valve actuator installed in the exhaust pipe, a bypass control valve that opens and closes by a bypass valve actuator installed in the bypass passage, a rotation sensor that detects an engine speed,
And a controller that operates the exhaust pipe valve actuator and the bypass valve actuator in response to a detection signal of the rotation sensor to control opening / closing operations of the exhaust pipe control valve and the bypass control valve.

[0015]

The exhaust gas treatment device according to the present invention is constructed as described above and operates as follows. That is, in this exhaust gas treatment device, a conductive and heat-resistant metal pipe having a large number of gas passages is installed in a case in which the metal pipe is installed in the exhaust passage in the longitudinal direction in the exhaust gas flow direction without being in contact with each other. , A pipe-shaped filter made of heat-resistant porous ceramics and having a closed downstream end is placed inside the metal pipe, and the ends of the metal pipe are electrically paired with a conductive connecting member. Since the metal pipes are connected and connected in series, and the metal pipes are energized by the electric power from the power supply source, a large number of the metal pipes can constitute a heater, and the filter is constantly heated by the metal pipes. , Carbon, soot, H collected by the filter
The particulates such as C are immediately burned into gas, the particulates are not excessively deposited in the filter, a local high temperature portion is not generated in the filter, and the filter is cracked, cracked, No damage such as burning will occur.

Since a generator for generating power by operating a turbocharger driven by the exhaust gas energy of the engine is used as a power supply source, a large amount of power is required to energize the metal pipe. The electric power supplied to the metal pipe is the electric power generated by the exhaust gas energy using the generator installed in the turbocharger, and there is no shortage of electric power and the collection function and incineration function of the filter are not deteriorated. . Therefore, electric power can be constantly supplied to the metal pipe, the filter can be constantly heated, and particulates such as carbon collected in the filter can be immediately incinerated, and excess carbon is deposited on the filter. Therefore, the filter does not become clogged.

Further, this exhaust gas treatment device is provided with a bypass passage bypassing a filter branched from an exhaust passage downstream of the turbocharger, and a bypass control valve which is opened and closed by a bypass valve actuator is provided in the bypass passage. At the command of the controller, when the engine is started, the flow of exhaust gas is made to flow through the filter of the exhaust gas treatment device, and the particulate matter such as carbon, soot, HC contained in the exhaust gas is controlled by the filter to rotate the engine. At high speed, the exhaust gas flow can be controlled so as to bypass the filter, and the particulate matter trapped in the filter can be always effectively removed from the filter.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of an exhaust gas treatment apparatus according to the present invention will be described below with reference to the drawings. FIG. 1 is a schematic explanatory view showing one embodiment of an exhaust gas treatment system for a diesel engine incorporating the exhaust gas treatment device according to the present invention,
FIG. 2 is a sectional view showing an embodiment of this exhaust gas treatment device,
FIG. 3 is an end view showing an end portion of the exhaust gas treatment device of FIG. 2, and FIG. 4 is a partially omitted sectional view showing a relationship between a metal pipe and a filter.

As shown in FIG. 1, an exhaust gas treating apparatus according to the present invention is generally designated by reference numeral 1 and is a DPF (diesel particulate filter) incorporated in an exhaust passage 2 of a diesel engine 3. In particular, the exhaust gas discharged from the diesel engine 3 is passed through the filter 4 arranged in the exhaust passage 2, and the particulates such as carbon, soot and HC contained in the exhaust gas are collected and collected. Filter 4 with red particulate heat
It incinerates into gas to purify exhaust gas.

A turbocharger 5 is connected to the exhaust manifold 23 of the diesel engine 3. The turbocharger 5 includes a turbine 7 driven by exhaust gas energy, a compressor 8 connected to the turbine 7 by a shaft 11, and a generator 6 (generally, a power generator) disposed on the shaft 11 and generating electric power by driving the turbine 7.・ Has an electric motor). The generator 6 has a shaft 11
It is composed of a permanent magnet 9 fixed to and an electromagnetic coil. The exhaust gas discharged from the turbocharger 5 is
It is exhausted to the outside through the exhaust passage 2. An exhaust gas treatment device 1 for purifying exhaust gas emitted from the engine 3 is incorporated in the exhaust passage 2.

This exhaust gas treatment apparatus 1 has a large number of pipe-shaped filters 4 made of porous ceramics capable of purifying exhaust gas, and the downstream end of each filter 4 is It is made of the same material and is integrally formed in a closed state, or is closed by a closure plug 16. The filters 4 are arranged in the outer case 20 of the exhaust gas treatment device 1 incorporated in the exhaust passage 2 so as to be separated from each other in the longitudinal direction in the flow direction of the exhaust gas. Each of the filters 4 has a metal pipe 2 whose outer peripheral surface is made of a conductive heat-resistant metal.
It is covered with 2. In particular, the filter 4 is made of porous ceramics and formed in a pipe shape, and the porous ceramics is selected from aluminum oxide Al ₂ O ₃ , aluminum titanate Al ₂ TiO ₅ , silicon nitride Si ₃ N ₄ and silicon carbide SiC. The ceramics is a porous sintered material having a porosity of substantially 40% to 50% or more and a through hole diameter of about 20 μm.

The metal pipes 22 are arranged in the case 20 so as to be longitudinally spaced from each other in the flow direction of the exhaust gas so as not to electrically short-circuit in a non-contact state. The metal pipe 22 is preferably positioned by the non-conductive spacer plates 26 provided at both ends. The spacing plate 26 is, for example, A
It can be made of heat resistant ceramics such as l ₂ O ₃ . Also,
The metal pipe 22 holds the filter 4 therein, but has a large number of gas passage holes 24. The metal pipe 22 is made of a Ni—Cr heat resistant metal such as incoloy. Further, the end portions of the metal pipes 22 are electrically connected to each other by the conductive connecting members 15 so that the adjacent end portions are electrically connected in series. That is, the pair of metal pipes 2
2 is electrically connected to each other by the connecting member 15 at one end and electrically connected to another metal pipe 22 by another connecting member 15 at the other end, as if each metal pipe 22 is connected. The members 15 are in a zigzag state at both ends.

The exhaust gas treatment device 1 includes an outer case 2
The inner wall surface of No. 0 is shielded by a heat shield material 19 such as alumina fiber, and a large number of metal pipes 22 are arranged in the interior thereof at intervals in the longitudinal direction. Therefore, both the filter 4 and the metal pipe 22 have a structure in which heat is shielded from the outside. A temperature sensor 13 is provided to detect the temperature of the filter 4 inside the case 20. The metal pipe 22 is connected to a conductor 14 in which a switch is installed in order to supply electric power from the generator 6.

In this exhaust gas treatment apparatus 1, if excessive particulates such as carbon, soot, and HC are deposited on the filter 4, the filter 4 will be overheated.
The amount of power supplied to the metal pipe 22 can be controlled while monitoring the temperature of the. That is, the detection signal from the temperature sensor 13 is input to the controller 10, and the controller 10 controls the power supply amount to the metal pipe 22 in response to the temperature detection signal and also controls the driving of the blower 12 to control the exhaust gas. The amount of air fed into the device 1 can be controlled. For example, when the load of the engine is high, the amount of particulates such as carbon contained in the exhaust gas is large and the temperature of the exhaust gas is high. In addition, since the electric power generated by the generator 6 of the turbocharger 5 becomes large when the engine is operating under a high load, if a part of the electric power is supplied, the particulates collected by the filter 4 will burn. It becomes a gas such as carbon dioxide and steam.

That is, in this exhaust gas treatment device, if the metal pipe 22 is constantly energized and the filter 4 is heated by the metal pipe 22 to make the filter 4 red hot, carbon, soot, The particulate matter such as HC is immediately incinerated, becomes a gas such as carbon dioxide gas, passes through the filter 4, and is released to the outside, so that the carbon deposition phenomenon inside the filter 4 does not occur. Therefore, since uneven deposition and uneven combustion of carbon in the filter 4 do not occur, the ceramics that constitute the filter 4 are cracked,
It is possible to prevent burning such as cracks. Further, when the carbon is deposited on the filter 4, that is, when the carbon is not collected by the filter 4, the controller 10 may perform control to turn off the switch.

If the ceramics of the above size is used as the ceramics of the filter 4, the exhaust gas of the diesel engine is exhausted through the pores, but the particulates such as carbon contained in the exhaust gas are filtered by the filter 4. Can be reliably collected with. That is, by flowing the exhaust gas from the opening 25 on the upstream side of the filter 4, the carbon contained in the exhaust gas is collected on the inner wall surface of the pipe of the filter 4 and is deposited there, but the exhaust gas does not pass through the filter wall surface. The gas passes through the gas passage hole 24 of the metal pipe 22, and then passes through the passage 17 between the metal pipe 22 and the metal pipe 22 to be discharged from the outlet 18 of the exhaust passage 2 to the outside.

Therefore, when the carbon collected on the inner wall surface of the pipe of the filter 4 conducts electricity to the metal pipe 22, the metal pipe 22 itself serves as a heater, and the filter 4 arranged inside the metal pipe 22 is heated. It heats up red,
The carbon burns there into carbon dioxide, which likewise passes through the wall of the filter, through the gas passages 24 in the metal pipe and through the passage 17 between the metal pipe 22 and the metal pipe 22. And is discharged from the outlet 18 of the exhaust passage 2 to the outside. Moreover, since the metal pipe 22 is almost always energized by a command from the controller 10, carbon is always incinerated immediately, and excess carbon is not deposited on the inner wall surface of the filter 4, and the filter itself is locally localized. It is not overheated.

Further, in order to burn the carbon in the exhaust gas collected by the filter 4, there is provided an electric power supply source for supplying electric power to the metal pipe 22 which is always energized. In this embodiment, the power supply source uses the generator 6 provided in the turbocharger 5 driven by the exhaust gas energy of the diesel engine 3. The generator 6 generates electricity by driving the turbine 7 of the turbocharger 5 with exhaust gas energy. A large amount of electric power is required to send electric power to the metal pipe 22, but the permanent magnet 9 is provided on the shaft 11 of the turbocharger 5.
If power is generated by the generator 6 consisting of, for example, 4 to 8 kw of electric power is generated, and since this electric power is converted from exhaust gas energy, there is no power loss and the metal pipe 22 can be efficiently used. Available.

Further, in the engine 3 equipped with the turbocharger 5, the smoke generation level is low except at the time of starting. Therefore, at the time of engine starting, the flow of exhaust gas is controlled so as to flow through the filter 4 of the exhaust gas processing apparatus 1. However, when the rotation speed of the engine 3 is large, that is, when the engine rotation speed is high,
The flow of exhaust gas can be controlled so as to bypass the filter 4 of the exhaust gas treatment device 1. in this way,
If the flow of exhaust gas to the filter 4 of the exhaust gas treatment device 1 is controlled according to the operating state of the engine 3, the filter 4
Particulates of carbon, soot, HC, etc. collected in the above are always effectively removed. In some cases, instead of detecting the engine speed, the engine load is detected as the engine operating state, the exhaust gas flow is bypassed through the filter 4 of the exhaust gas treatment device 1 when the load is low, and the exhaust gas flow when the load is high is detected. The flow can be controlled to flow through the filter 4 of the exhaust gas treatment device 1.

When the flow of exhaust gas is controlled according to the operating state of the engine 3 as described above, an exhaust system system incorporated in the exhaust gas processing apparatus 1 is constructed as shown in FIG. You can That is, turbocharger 5
The downstream exhaust passage 2 includes an exhaust pipe 35 that communicates with the filter 4 of the exhaust gas treatment device 1 and a bypass passage 34 that bypasses the filter 4 that branches from the exhaust passage 2. The exhaust pipe 35 is provided with an exhaust pipe control valve 33 operated by the exhaust pipe valve actuator 31 in order to open and close the passage. Further, the bypass passage 34 is provided with a bypass control valve 30 operated by the bypass valve actuator 32 in order to open and close the passage. Further, the engine 3 is provided with a rotation sensor 36 for detecting the engine speed. In response to the detection signal from the rotation sensor 36, the controller 10 operates the exhaust pipe valve actuator 31 to control the opening / closing operation of the exhaust pipe control valve 33, and operates the bypass valve actuator 32 to open / close the bypass control valve 30. Control operation.

Controller 10 of this exhaust gas treatment device
An example of the operation processing according to the command will be described. The rotation signal detected by the rotation sensor 36, that is, the engine speed N
Is input to the controller 10. Therefore, the controller 10 compares and judges the detection signal from the rotation sensor 36, that is, the engine rotation speed N and the preset rotation speed N ₀ ,
When the engine speed N is higher than the set speed N ₀ ,
Since the generation of particulates such as smoke is low, it is not necessary to collect the exhaust gas from the engine 3 through the filter 4 of the exhaust gas treatment device 1 to collect the particulates. Therefore, in response to a command from the controller 10, the bypass valve actuator 32 is operated to open the bypass control valve 30, and the exhaust pipe valve actuator 31 is operated to close the exhaust pipe control valve 33. Therefore, the exhaust gas discharged from the turbocharger 5 flows through the bypass passage 34 and bypasses the filter 4 of the exhaust gas processing device 1. Therefore, if the electric power from the generator 6 is supplied to the exhaust gas treatment device 1 for a predetermined time, the particulates such as carbon, soot, and HC that have been captured by the filter 4 up to now are quickly incinerated and effectively. The exhaust gas is removed, and the filter 4 is restored to a state in which it can collect good particulates.

When the engine speed N is smaller than the set speed N ₀ according to the comparison judgment of the controller 10, it is at the time of engine start and the like, and there are many particulates such as smoke, so the exhaust gas from the engine 3 is exhausted. It is necessary to collect particulates through the filter 4 of the gas treatment device 1. Therefore, the exhaust pipe valve actuator 3
1 is operated to open the exhaust pipe control valve 33, and the bypass valve actuator 32 is operated to close the bypass control valve 30. Therefore, the exhaust gas discharged from the turbocharger 5 flows through the exhaust pipe 35,
The exhaust gas treatment device 1 is made to flow to the filter 4 so that the filter 4
Particulates are collected at. Therefore, the electric power from the generator 6 is supplied to the exhaust gas treatment device 1, and the filter 4 is red-heated to quickly incinerate the particulates such as carbon, soot, and HC collected by the filter 4 to be exhausted. .

Further, in the exhaust gas treatment device 1, in order to activate the combustion of the carbon collected in the filter 4, a blower device for sending air to the filter 4 to the exhaust passage 2 upstream from the installation position of the filter 4. 12 are provided. The blower device 12 can be configured to be driven by the supply of electric power from the generator 6 provided in the turbocharger 5. Also,
In the drawing of this embodiment, a configuration is shown in which a blower device 12 is separately provided, but it is needless to say that the blower device 12 is not provided and combustion air is introduced from the compressor 8 of the turbocharger 5. You can also

[0034]

The exhaust gas treatment device according to the present invention is constructed as described above and has the following effects.
That is, in this exhaust gas treatment device, conductive and heat-resistant metal pipes having a large number of gas passages are placed in a case in a non-contact state with each other, and one end portion made of heat-resistant porous ceramics is used. The sealed pipe-shaped filter is arranged inside the metal pipe, and the ends of the metal pipe are electrically connected to each other in pairs by a conductive connecting member to connect the metal pipes in series to supply power. Since the metal pipe is constantly energized by the electric power from the source, a large number of the metal pipes can form a continuous heater, the metal pipes constantly heat the filter, and the particulates such as carbon trapped by the filter. Burns immediately,
It becomes a gas such as carbon dioxide, steam, etc., and is discharged through the filter. Therefore, particulates are not excessively deposited in the filter, a local high temperature portion is not generated in the filter, and the filter is free from damage such as cracks and burnout. Reliability,
The durability can be improved.

Further, in this exhaust gas treatment apparatus, since the generator for generating power by the operation of the turbocharger driven by the exhaust gas energy of the engine is used as a power supply source, a large amount of electric power is supplied to energize the metal pipe. The electric power supplied to the metal pipe is the electric power generated by the exhaust gas energy using the generator installed in the turbocharger, and the electric power is insufficient to deteriorate the filtering function of the filter. There is no loss of power to the engine. Moreover, since the metal pipe has electric power capable of constantly flowing current, the filter is always heated, and excessive particulates are not deposited on the filter, and the filter is clogged. Without causing a high temperature part locally, the ceramic of the filter is burned,
It will not be damaged.

Further, a bypass passage for bypassing a filter branched from the exhaust passage downstream of the turbocharger is provided, and a bypass control valve is provided in the bypass passage. When the engine is started, the exhaust gas flow is controlled by the exhaust gas treatment device. Exhaust gas treatment is performed by flowing it through the filter, but at high speeds, the flow of exhaust gas is controlled so as to bypass the filter, and particulates trapped in the filter are always effectively removed from the filter. Control can also be performed.

Further, in this exhaust gas treatment device, the porous ceramics constituting the filter is Al ₂
It is made of a ceramic selected from O ₃ , Al ₂ TiO ₅ , Si ₃ N ₄ , and SiC, and the ceramic has a porosity of substantially 50% or more and a through hole diameter of 20.
If it is made to have a size of about μm, it can exhibit high temperature strength sufficient to incinerate particulates such as carbon, and also sufficiently collects undesirable particulates such as carbon contained in the exhaust gas of diesel engines. be able to. Further, when the metal pipe is made of a Ni—Cr heat-resistant metal, the function as a heater can be sufficiently fulfilled by supplying electricity to the metal pipe, and the filter is sufficiently held at high temperature. be able to.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view showing an embodiment of an exhaust gas treatment system for a diesel engine incorporating an exhaust gas treatment device according to the present invention.

FIG. 2 is a cross-sectional view showing an embodiment of this exhaust gas treatment device.

FIG. 3 is an end view showing an end portion of the exhaust gas treatment device of FIG.

FIG. 4 is a cross-sectional view showing a relationship between a metal pipe and a filter of the exhaust gas treatment device of FIG.

[Explanation of symbols]

 1 Exhaust Gas Treatment Device 2 Exhaust Passage 3 Diesel Engine (Engine) 4 Filter 5 Turbocharger 6 Generator 15 Connection Member 17 Gas Passage 20 Case 22 Metal Pipe 24 Gas Through Hole 30 Bypass Control Valve 31 Bypass Valve Actuator 32 Exhaust Pipe Valve Actuator 33 Exhaust pipe control valve 34 Bypass passage 35 Exhaust pipe 36 Rotation sensor

Claims (5)

[Claims] 1. A conductive and heat-resistant metal pipe, which is arranged in a non-contact state in a longitudinal direction in a flow direction of exhaust gas in a case incorporated in an exhaust passage and has a large number of gas passages formed therein. A pipe-shaped filter which is disposed inside and made of heat-resistant porous ceramics and whose downstream end is closed, and the ends of the metal pipes are electrically paired and connected, and the metal pipes are connected in series. An exhaust gas treatment device comprising: a plurality of electrically conductive connecting members, and an electric power supply source that supplies electric power to the metal pipe to burn particulates collected by the filter. 2. The power supply source is constituted by a generator that generates electric power by operating a turbocharger driven by the exhaust gas energy of the engine.
The exhaust gas treatment device according to. 3. The porous ceramics constituting the filter is SiC, Si ₃ N ₄ , Al ₂ O ₃ , Al ₂
The exhaust gas treatment device according to claim 1, wherein the exhaust gas treatment device is a ceramic selected from TiO ₅ , has a porosity of about 50% or more, and has a through hole diameter of about 20 μm. 4. The exhaust gas treatment device according to claim 1, wherein the metal pipe is made of a refractory metal of Ni or Cr type. 5. A plurality of pipe-shaped members which are separated from each other in a non-contact state in the longitudinal direction in the exhaust gas flow direction in a case incorporated in an exhaust pipe communicating with an exhaust passage downstream of a turbocharger provided in an engine. A filter, a power supply source that supplies power to a metal pipe that heats the filter to incinerate particulates collected by the filter, a bypass passage that bypasses the filter branched from the exhaust passage, and an exhaust pipe installed An exhaust pipe control valve that opens and closes with the exhaust pipe valve actuator, a bypass control valve that opens and closes with a bypass valve actuator installed in the bypass passage, a rotation sensor that detects an engine speed, and a response signal from the rotation sensor. The exhaust pipe valve actuator and the bypass valve actuator The exhaust gas treatment device according to claim 1, further comprising a controller that controls the opening and closing operations of the exhaust pipe control valve and the bypass control valve by operating the exhaust gas control valve.