JP2007309183A - Exhaust gas treatment device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To effectively purify exhaust gas while inhibiting ill influence such as a rise of exhaust pressure by using electrostatic separation action. <P>SOLUTION: An electrostatic separation device 3 and an exhaust gas after-treatment device 4 are installed in an exhaust passage 2 of an internal combustion engine 1. The electrostatic separation device 3 is provided with a dust collection function charging and capturing PM in exhaust gas flowing in the exhaust passage 2 by corona discharge. PM collected by the electrostatic separation device 3 is introduced to a PM treatment device 7 via a communication path 5 and converted. Heat discharged from the PM treatment device 7 is guided to the after-treatment device 4 together with exhaust gas via the communication path 5 and is used for treatment in the exhaust gas after-treatment device 4. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an exhaust treatment device for treating a gas (exhaust gas) discharged from a combustion device and containing various exhaust substances.

  Purifying the exhaust from the combustion device to suppress the expansion of air pollution is an important issue. For example, regarding diesel combustion engines, PM (particulate matter: particulate matter = mainly black smoke) in the exhaust (Soot), unburned fuel called SOF, components of lubricating oil, and components generated from sulfur in light oil fuel called sulfate) and NOx (nitrogen oxide) emissions are so-called trade Up to now, it has been necessary to mount exhaust treatment devices for both PM and NOx to suppress the emission of these regulated substances.

As an exhaust treatment device for reducing the emission amount of PM into the atmosphere, for example, a diesel particulate filter is installed in the exhaust passage, and the exhaust gas is exhausted by passing through the diesel particulate filter. There is something that collects PM. However, since this is collected by a filter, there is a risk that exhaust pressure will increase and combustion efficiency will be lowered.
For this reason, for example, when a predetermined operation time has elapsed or when a predetermined exhaust pressure is reached, it is necessary to regenerate the diesel particulate filter. As a method for regenerating an existing diesel particulate filter, for example, there is a method for promoting oxidation of PM collected by the effect of a noble metal catalyst.

  As another regeneration method, the engine side is controlled, so-called fuel post-injection (injection performed after main injection in one combustion, unburned hydrocarbon HC together with exhaust without being burned in the cylinder) Fuel injection aiming to be supplied to the diesel particulate filter), the unburned hydrocarbons are supplied to the diesel particulate filter together with the exhaust gas, and reacted on the catalyst carried on the diesel particulate filter. A method of burning (oxidizing) PM using the reaction heat is known.

Further, there is a method of performing a predetermined process on exhaust using a reformed gas obtained by fuel reforming by a method such as adding fuel to an exhaust passage as an additive of an exhaust treatment catalyst. In such a method, in order to obtain a fuel reforming reaction effectively, it is necessary to raise and maintain the temperature of the catalyst to, for example, 600 ° C. or higher.
However, in each of the above-described methods, when the exhaust gas flow rate is large, the amount of heat taken away by the exhaust gas increases, so that it is difficult to efficiently raise or maintain the temperature of the catalyst.

Here, Patent Document 1 discloses a technique of disposing a metal rod or the like in the center of a metal pipe and applying a high voltage between both electrodes of the metal pipe and the metal bar as an electrostatic collection and electrostatic separation technique. ing. This collects PM in the vicinity of the inner wall of the metal pipe by the action of electrostatic dust collection, and enables separation of the PM near the inner wall of the metal pipe and the vicinity of the center of the metal pipe. And it can separate into the gas flow which concentrated PM, and the gas flow which hardly contains PM by arranging piping of the double pipe structure in the latter part of such PM collection and separation part. it can.
Japanese Patent Laying-Open No. 2005-076497

  The present invention has been made in view of the above circumstances, and includes, for example, simultaneously reducing both substances such as PM and NOx while suppressing adverse effects such as an increase in exhaust pressure using an electrostatic separation action. An object of the present invention is to provide an exhaust treatment device capable of effectively purifying exhaust gas.

Therefore, the exhaust treatment device according to the present invention is
An exhaust treatment device for a combustion device that causes combustion and discharges a gas containing an electrostatically separable substance through an exhaust passage,
An electrostatic separation means that introduces at least a part of a gas containing an electrostatically separable substance that is interposed in the exhaust passage and is discharged from the combustion device, and electrostatically separates the substance contained in the gas;
Predetermined with respect to substances introduced and introduced into the exhaust passage on the downstream side of the electrostatic separation means (concepts including other substances and gases as well as substances capable of electrostatic separation. The same applies hereinafter). First exhaust processing means for performing the processing of
An exhaust gas diversion passage for guiding at least a part of the gas containing the substance electrostatically separated by the electrostatic separation means to the first exhaust treatment means through a route different from the exhaust passage;
A second exhaust treatment means interposed in the exhaust shunt passage and performing a predetermined treatment on the substance to be introduced;
Constructed including.

  The predetermined processing in the first exhaust processing means is efficiently performed under conditions of a predetermined temperature or higher.

  The predetermined treatment in the first exhaust treatment means includes at least one of a treatment for purifying NOx or an oxidation treatment for a substance to be introduced.

  The predetermined processing in the second exhaust processing means is efficiently performed under conditions of a predetermined temperature or higher.

  The predetermined process in the second exhaust treatment means includes at least one of a process for reducing NOx, an oxidation process for a substance to be introduced, or a reforming process for modifying a substance to be introduced. Features.

  The exhaust treatment apparatus according to the present invention includes a third exhaust treatment unit that is interposed in the exhaust diversion passage on the downstream side or the upstream side of the second exhaust treatment unit and performs a predetermined treatment on the introduced substance. Furthermore, it can comprise.

  The predetermined process in the third exhaust processing unit is a predetermined process different from that of the second exhaust unit, and the process is efficiently performed under a condition of a predetermined temperature or higher, or the temperature of the substance to be introduced is set. It includes at least one process of predetermined temperature rising or maintaining.

  Further, a flow rate control means for controlling the flow rate can be disposed in the exhaust branch passage.

  According to the present invention, the exhaust gas is effectively purified including the simultaneous reduction of both substances such as PM and NOx while suppressing adverse effects such as an increase in exhaust pressure using the electrostatic separation action. Can be processed.

  Hereinafter, embodiments of an exhaust treatment apparatus according to the present invention will be described in detail with reference to the accompanying drawings. The present invention is not limited to the examples described below.

A first embodiment of an exhaust treatment apparatus according to the present invention will be described with reference to FIGS.
The internal combustion engine 1 shown in FIG. 1 can be, for example, a diesel engine that performs diesel combustion, but is not limited to this, and any other combustion engine that includes exhaust gas may be a gasoline engine or other internal combustion engine. Regardless of the combustion method, any mobile or stationary combustion device can be used.

  As shown in FIG. 1, an exhaust passage 2 is connected to the internal combustion engine 1, and an electrostatic separation device 3 is interposed in the exhaust passage 2, and an exhaust aftertreatment device 4 is disposed downstream of the exhaust. Is intervening.

  As shown in FIGS. 2 and 3, the electrostatic separation device 3 has, for example, a cylindrical shape (a hollow shape having a desired longitudinal cross-sectional shape such as an ellipse or a rectangle in addition to a cylinder). The low-voltage electrode portion 3A includes a high-voltage electrode portion 3B extending in the longitudinal direction in the vicinity of the central axis in the longitudinal direction, and an inner cylinder portion 3C. Here, the electrostatic separation device 3 corresponds to the electrostatic separation means according to the present invention.

  The low voltage electrode unit 3A is made of a conductor such as a metal such as stainless steel. The electrostatic separation device 3 according to the first embodiment includes a high voltage electrode unit 3B and a low voltage electrode unit 3A described later. And a dust collecting function for charging and capturing PM (particulate matter) 10 in the exhaust gas 6 flowing in the exhaust passage 2 by corona discharge generated by a high voltage applied between them.

  The high voltage electrode portion 3B is a discharge electrode (corona discharge electrode) that generates a corona discharge with the low voltage electrode portion 3A, and is composed of, for example, a stainless wire, a piano wire, a fine wire, a stranded wire, a rod-like member, or the like. be able to. The cross section of the high voltage electrode portion 3B in a direction substantially orthogonal to the longitudinal direction of the low voltage electrode portion 3A can be formed in a desired shape such as a round shape, an oval shape, or a square shape. A material having conductivity can be used. For example, a material having excellent corrosion resistance such as SUS (stainless steel), tungsten, nickel, titanium, and Inconel can be used.

  The inner cylinder portion 3C is an exhaust shunt member having a cylindrical shape (the cross-sectional shape in the longitudinal direction can be a desired shape in addition to a round shape, an oval shape, and a square shape). High concentration exhaust gas 6A containing a large amount of PM10 collected near the inner wall of the low voltage electrode portion 3A by corona discharge between the electrode portion 3B and low concentration exhaust gas 6B having a low concentration of PM10 inside can be separated. In addition, as shown in FIG. 2, the low voltage electrode portion 3B is disposed substantially concentrically with the low voltage electrode portion 3B on the exhaust downstream side of the low voltage electrode portion 3B. The inner cylinder portion 3C does not need to be a conductive member, and can be formed of an appropriate material such as metal, ceramic, or resin.

  In the present embodiment, the inner cylinder portion 3C is connected to an exhaust passage 2 communicating with an exhaust aftertreatment device 4 described later at the most downstream portion of the exhaust. For example, as shown in FIG. It is also possible to provide an opening 3D configured by cutting out a part of the circumference so that the high concentration exhaust 6A can be returned to the exhaust passage 2.

  The exhaust aftertreatment device 4 functions as the first exhaust treatment means according to the present invention. For example, the NOx occlusion reduction three-way catalyst, the DPNR catalyst (the NOx occlusion reduction three-way catalyst is added to the porous ceramic structure). Combining the exhaust gas through the ceramic gap, the catalyst oxidizes and reduces with a catalyst that can greatly reduce PM and NOx), the catalyst for HC-SCR (using hydrocarbon as a reducing agent) Selective reduction type NOx catalyst that purifies NOx), urea SCR (UREA-SCR) catalyst (selective reduction type NOx catalyst that purifies NOx using urea as a reducing agent), diesel particulate filter, etc. Can be adopted as appropriate.

  Note that the exhaust aftertreatment device 4 has, for example, characteristics of exhaust gas flowing out to the exhaust downstream side through the inner cylinder portion 3C of the electrostatic separation device 3 (NOx, CO, HC, PM contained in the exhaust gas). Depending on the emission amount / ratio of each component, etc., it is determined whether to use any or all of the above-mentioned various types of catalysts or filters, or to combine a plurality of them regardless of whether they are the same or different. can do.

  In this embodiment, in addition to the exhaust passage 2, a communication passage 5 that communicates the electrostatic separation device 3 and the exhaust post-treatment device 4 is provided. The communication path 5 exhausts at least a part of the high-concentration exhaust 6A containing a large amount of PM10 collected near the inner wall of the low-voltage electrode part 3A by corona discharge between the low-voltage electrode part 3A and the high-voltage electrode part 3B. It is arranged to be able to flow into the post-processing device 4. Such a communication path 5 corresponds to an exhaust gas distribution path according to the present invention.

  As shown in FIG. 1, a PM processing device 7 is interposed in the communication path 5. This PM processing device 7 functions as one of the second exhaust processing means according to the present invention, and purifies PM 10 contained in the high concentration exhaust 6A flowing into the PM processing device 7 through the communication path 5. For example, a DPNR catalyst (a combination of a porous ceramic structure and a NOx occlusion reduction type three-way catalyst is used to oxidize or reduce the exhaust while passing through a gap in the ceramic. , A catalyst that can greatly reduce PM and NOx), a diesel particulate filter, and the like, can be used as required.

  In such a PM processing apparatus 7, for example, the PM 10 is oxidized by a heating method using a part (including an appropriate combination thereof) or all of fuel addition burner, heater, fuel addition, catalyst, plasma, fuel post injection, etc. And remove. The PM processing device 7 is not limited to the above as long as it can oxidize PM10. For example, the PM processing device 7 does not include a collecting means such as a diesel particulate filter, and includes a fuel addition burner, a heater, a catalyst, and the like. It can also be constituted by a temperature raising means.

  As described above, in the present embodiment, only the high-concentration exhaust 6A out of the exhaust from the internal combustion engine 1 is introduced into the communication passage 5, so that the PM 10 can be efficiently captured while suppressing adverse effects such as an increase in exhaust pressure. Since only the high-concentration exhaust gas 6A passes through the PM processing device 7, the exhaust gas flow rate is small, and hence the amount of heat taken away by the exhaust gas can be reduced. Therefore, the regeneration of the PM processing device 7 (oxidation of PM10) , The temperature of the portion (for example, catalyst) that contributes to combustion can be effectively increased or maintained.

  For this reason, for example, the temperature raising means such as the fuel addition burner, the heater, the fuel addition, the catalyst, the plasma, and the fuel post injection can be reduced in size (reduced capacity) and reduced in weight, and may be omitted in some cases. It is possible to reduce the cost.

  Furthermore, in the present embodiment, the heat discarded from the PM processing device 7 is not released to the outside as it is, but via the exhaust flowing through the communication path 5 to the exhaust aftertreatment device 4 disposed on the exhaust downstream side. Therefore, the heat discarded from the PM processing device 7 can be effectively used in the post-processing (for example, NOx purification) in the exhaust post-processing device 4, so that, for example, NOx is effective. Can be reduced.

  For this reason, it is possible to efficiently perform the after-treatment in the exhaust aftertreatment device 4, and when the exhaust aftertreatment device 4 is provided with a temperature raising means, the temperature raising means can be downsized (smaller). (Capacitance) and weight can be reduced, and in some cases, it can be omitted, and the cost can be reduced.

  That is, according to the present embodiment, the PM 10 can be effectively removed by the PM processing device 7 while suppressing an adverse effect such as an increase in exhaust pressure, while having a simple and inexpensive configuration, and at the same time after exhaust. For example, NOx can be effectively purified by the processing device 4.

  A second embodiment of the exhaust treatment apparatus according to the present invention will be described with reference to FIG. As shown in FIG. 4, an exhaust passage 2 is connected to the internal combustion engine 1 as in the first embodiment, and an electrostatic separation device 3 is interposed in the exhaust passage 2, and the exhaust downstream side thereof. An exhaust aftertreatment device 4 is interposed in the exhaust gas. In addition, the same code | symbol is attached | subjected to the element similar to Example 1, and detailed description is abbreviate | omitted.

  In the present embodiment, in addition to the exhaust passage 2, a communication passage 5 that communicates the electrostatic separation device 3 and the exhaust aftertreatment device 4 is disposed, and the communication passage 5 includes a reformer 8 ( For example, Japanese Patent Laid-Open No. 2005-098226 is provided.

This reformer 8 functions as one of the second exhaust treatment means according to the present invention, and can be composed of, for example, any one of a burner type, a plasma type, a catalytic type, or a combination thereof, It acts on the high-concentration exhaust 6A flowing through the communication passage 5 to promote the combustion of the PM 10, and efficiently generates a highly ignitable gas or a highly combustible gas (including radicals). For reforming, a fuel addition means 8A may be provided to add a small amount of fuel. In the reformer 8, for example, the following reaction can be expected.
HC → CO, H ₂ , R—CHO, R—OH

  By the way, in the electrostatic separation apparatus 3, it is also possible to separate or activate gases, liquids, and solids other than PM10 according to the charge amount. Therefore, the substance advantageous for the reforming reaction and the substance disadvantageous for the reforming reaction are separated by the action of electrostatic separation, and the substance advantageous for the reforming reaction is effectively sent to the reforming device 4. It is also possible to enhance the reforming effect. It should be noted that a heat exchanger is provided on the exhaust upstream side of the electrostatic separation device 3 or inside thereof, and the temperature of the exhaust gas introduced into the electrostatic separation device 3 is controlled as desired, so that the separation action can be made more effective. Can also be performed. Moreover, it is also possible to configure so that the temperature of the exhaust gas introduced into the electrostatic separation device 3 is controlled as desired by introducing outside air into the communication path 5.

  In this embodiment, the reformed exhaust gas is introduced and added to the exhaust gas aftertreatment device 4 via the communication passage 5 to increase the efficiency of the post-treatment (for example, NOx purification) in the exhaust gas aftertreatment device 4. Thus, for example, NOx is effectively reduced.

  Thus, in the present embodiment, only the high concentration exhaust gas (including the concept of exhaust gas containing a lot of substances advantageous for the reforming reaction) 6A among the exhaust gas from the internal combustion engine 1 is connected to the communication path 5. Therefore, the reformer 8 can efficiently reform while suppressing adverse effects such as an increase in exhaust pressure, and only the high-concentration exhaust 6A passes through the reformer 8, so the exhaust flow rate is high. Therefore, the amount of heat removed by the exhaust gas can be reduced, and the temperature of the portion contributing to the reforming of the reformer 8 can be effectively raised or maintained.

For this reason, the reformer 8 can be reduced in size (smaller capacity), reduced in weight, and further reduced in cost.
Further, in the present embodiment, the exhaust gas reformed and heated in the reformer 8 is not discharged to the outside as it is, but is connected to the exhaust aftertreatment device 4 disposed on the exhaust downstream side via the communication path 5. Therefore, the heat discarded from the reforming device 8 can be used effectively in the post-processing in the exhaust after-treatment device 4.

  For this reason, it is possible to efficiently perform the after-treatment in the exhaust aftertreatment device 4, and when the exhaust aftertreatment device 4 is provided with a temperature raising means, the temperature raising means can be downsized (smaller). (Capacitance) and weight can be reduced, and in some cases, it can be omitted, and the cost can be reduced.

  That is, according to the present embodiment, the PM 10 is effectively removed by reforming effectively by the reforming device 8 while suppressing adverse effects such as an increase in exhaust pressure while having a simple and inexpensive configuration. At the same time, the exhaust aftertreatment device 4 can effectively purify, for example, NOx.

By the way, a heat exchange device (not shown) is interposed in the communication path 5 between the reformer 8 and the exhaust aftertreatment device 4, and thereby the temperature of the exhaust led to the exhaust aftertreatment device 4 is set to a predetermined temperature. It may be controlled. Furthermore, it is also possible to take out heat from this heat exchange device and use it in other parts.
In the present embodiment, the reforming device 8 is taken as an example, but other processing devices may be interposed depending on the purpose.

  A third embodiment of the exhaust treatment apparatus according to the present invention will be described with reference to FIG. As shown in FIG. 5, an exhaust passage 2 is connected to the internal combustion engine 1 in the same manner as in the first and second embodiments, and an electrostatic separation device 3 is interposed in the exhaust passage 2, and its exhaust An exhaust aftertreatment device 4 is interposed on the downstream side. In addition, the same code | symbol is attached | subjected to the element similar to Example 1, 2, and detailed description is abbreviate | omitted.

In the present embodiment, in addition to the exhaust passage 2, a communication passage 5 that communicates the electrostatic separation device 3 and the exhaust post-treatment device 4 is disposed. The communication passage 5 includes the PM processing device 7 and the communication passage 5. The reformer 8 is interposed in this order toward the exhaust downstream side. However, it is of course possible to arrange them in a single case and integrally form them in appearance.
Here, the PM processing device 7 corresponds to the second or third exhaust processing means according to the present invention, and the reforming device 8 corresponds to the third or second exhaust processing means according to the present invention.

  The PM processing device 7 is a device having a function of purifying PM 10 contained in the high-concentration exhaust 6A flowing into the PM processing device 7 through the communication path 5, for example, a DPNR catalyst (in a porous ceramic structure). , NOx occlusion reduction type three-way catalyst, which is a catalyst that can significantly reduce PM and NOx by oxidizing and reducing with exhaust gas while passing through the gap between ceramics), diesel particulate filter, etc. It can be employed as appropriate according to the requirements.

  In such a PM processing apparatus 7, for example, the PM 10 is oxidized by a heating method using a part (including an appropriate combination thereof) or all of fuel addition burner, heater, fuel addition, catalyst, plasma, fuel post injection, etc. And remove. The PM processing device 7 is not limited to the above as long as it can oxidize PM10. For example, the PM processing device 7 does not include a collecting means such as a diesel particulate filter, and includes a fuel addition burner, a heater, a catalyst, and the like. It can also be constituted by a temperature raising means.

  The reformer 8 can be constituted by, for example, a burner type, a plasma type, a catalytic type, or a combination thereof, and acts on the high-concentration exhaust 6A flowing through the communication path 5 to promote the combustion of PM10. In addition, a highly ignitable gas or a highly combustible gas (including radicals) is efficiently generated. As in the second embodiment, a fuel addition means 8A may be provided for reforming to add a small amount of fuel.

  Thus, in the present embodiment, only the high concentration exhaust gas (including the concept of exhaust gas containing a lot of substances advantageous for the reforming reaction) 6A among the exhaust gas from the internal combustion engine 1 is connected to the communication path 5. Therefore, PM10 can be efficiently removed while suppressing adverse effects such as an increase in exhaust pressure, and only the high concentration exhaust gas 6A passes through the PM processing device 7, so that the exhaust flow rate is small, and therefore the exhaust gas is exhausted. Therefore, the temperature of the portion (for example, catalyst) that contributes to regeneration (PM10 oxidation and combustion) of the PM processing device 7 can be effectively increased or maintained.

  For this reason, for example, the temperature raising means such as the fuel addition burner, the heater, the fuel addition, the catalyst, the plasma, and the fuel post injection can be reduced in size (reduced capacity) and reduced in weight, and may be omitted in some cases. It is possible to reduce the cost.

  Further, in this embodiment, the heat discarded from the PM processing device 7 is guided to the reforming device 8 disposed on the downstream side of the exhaust through the exhaust without being released to the outside as it is. The heat discarded from the PM processing device 7 can be effectively used for the reforming process in the reforming device 8.

  For this reason, the reforming process in the reforming apparatus 8 can be performed efficiently, and when the reforming apparatus 8 is provided with a temperature raising means, the temperature raising means can be downsized (small capacity). In addition, the weight can be reduced, and in some cases, the weight can be omitted, and the cost can be reduced.

  In this embodiment, the reformed exhaust gas is introduced and added to the exhaust gas aftertreatment device 4 via the communication passage 5 to increase the efficiency of the post-treatment (for example, NOx purification) in the exhaust gas aftertreatment device 4. Thus, for example, NOx is effectively reduced.

  As described above, in the present embodiment, only the high concentration exhaust 6A out of the exhaust from the internal combustion engine 1 is introduced into the communication passage 5, so that the PM 10 can be efficiently burned in the PM processing device 7 and the reforming device 8. Since only the high-concentration exhaust 6A passes through the PM processing device 7 and the reforming device 8, the exhaust flow rate is small, and therefore the amount of heat taken away by the exhaust can be reduced. Thus, it is possible to effectively increase or maintain the temperature of the portion that contributes to each process of No. 8.

  Accordingly, the PM processing device 7 and the reforming device 8 can be reduced in size (reduced capacity), reduced in weight, and further reduced in cost.

  In the present embodiment, the exhaust gas that has been reformed and heated in the reformer 8 is not discharged to the outside as it is, but is connected to the exhaust aftertreatment device 4 disposed on the exhaust downstream side via the communication path 5. Therefore, the heat discarded from the reforming device 8 can be used effectively in the post-processing in the exhaust after-treatment device 4.

  For this reason, it is possible to efficiently perform the after-treatment in the exhaust aftertreatment device 4, and when the exhaust aftertreatment device 4 is provided with a temperature raising means, the temperature raising means can be downsized (smaller). (Capacitance) and weight can be reduced, and in some cases, it can be omitted, and the cost can be reduced.

  That is, according to the present embodiment, the PM 10 can be effectively removed by the PM processing device 7 and the reforming device 8 while suppressing adverse effects such as an increase in exhaust pressure, while having a simple and inexpensive configuration. At the same time, for example, NOx can be effectively purified by the exhaust aftertreatment device 4.

  By the way, a heat exchange device (not shown) is interposed in the communication path 5 between the reformer 8 and the exhaust aftertreatment device 4, and thereby the temperature of the exhaust led to the exhaust aftertreatment device 4 is set to a predetermined temperature. It may be controlled. Furthermore, it is also possible to take out heat from this heat exchange device and use it in other parts.

  In the present embodiment, the PM processing device 7 and the reforming device 8 have been described using an example in which the PM processing device 7 and the reforming device 8 are separately provided with the communication path 5 interposed therebetween. However, in the present embodiment, the PM processing device 7, It is also possible to adopt an apparatus in which the reformer 8 is configured integrally or continuously without using the communication path 5. In this embodiment, the PM processing device 7 and the reforming device 8 are taken as examples, but other processing devices may be interposed depending on the purpose.

  A fourth embodiment of the exhaust treatment apparatus according to the present invention will be described with reference to FIGS. As shown in FIGS. 6 and 7, the exhaust treatment apparatus according to the present embodiment is the same as the exhaust treatment apparatus according to each of the embodiments described above, except that the flow rate control means 9 is provided. Description of common parts is omitted.

  As shown in FIG. 6, when the present embodiment is applied to the first and second embodiments described above, the flow rate control means 9 including a throttle valve or the like is connected to the PM processing device 7 ( Alternatively, it is interposed between the reformer 8) and the exhaust aftertreatment device 4.

  Then, the flow rate control means 9 operates, for example, the operation of the internal combustion engine 1 based on a signal from an ECU (Engine Control Unit) or the like so that a desired process is achieved in the PM processing apparatus 7 (or the reforming apparatus 8). The exhaust flow rate flowing through the communication path 5 is controlled according to the state or the processing state in the PM processing device 7 (or the reforming device 8).

  The flow rate control means 9 can increase or change the arrangement position as appropriate, as indicated by a broken line in FIG.

  As shown in FIG. 7, when the present embodiment is applied to the above-described third embodiment, the flow rate control means 9 including a throttle valve or the like is provided with the reforming device 8 for the communication path 5. And the exhaust aftertreatment device 4.

  Then, the flow rate control means 9 is, for example, the operating state of the internal combustion engine 1 or the PM processing device based on a signal from the ECU or the like so that the desired processing is achieved in the PM processing device 7 (or the reforming device 8). 7 (or the reformer 8) controls the flow rate of exhaust gas flowing through the communication passage 5 in accordance with the processing state and the like.

In addition, as shown by the broken line in FIG. 7, the flow control means 9 can increase or change the arrangement position as appropriate.
According to the present embodiment, the exhaust flow rate flowing through the communication passage 5 can be controlled in accordance with the operating state of the internal combustion engine 1 or the processing state in the PM processing device 7 (or reforming device 8). The treatment in the apparatus 7 or the reforming apparatus 8 can be made more effective.

It is a figure which shows the structural example of the exhaust-gas treatment apparatus of Example 1 which concerns on this invention. It is sectional drawing which shows the structural example of the electrostatic separation apparatus which concerns on an Example same as the above. It is a XX direction arrow line view in FIG. It is a figure which shows the structural example of the exhaust-gas treatment apparatus of Example 2 which concerns on this invention. It is a figure which shows the structural example of the exhaust-gas treatment apparatus of Example 3 which concerns on this invention. It is a figure which shows the structural example of the exhaust-gas treatment apparatus of Example 4 which concerns on this invention. It is a figure explaining the other structural example of an Example same as the above.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Internal combustion engine 2 Exhaust passage 3 Electrostatic separation device 3A Low voltage electrode part 3B High voltage electrode part 3C Inner cylinder part 4 Exhaust treatment device 5 Communication path 6 Exhaust 6A High concentration exhaust gas 6B Low concentration exhaust gas 7 PM processing device 8 Reformer 9 Flow control means 10 PM (Particulate Matter)

Claims (8)

An exhaust treatment device for a combustion device that causes combustion and discharges a gas containing an electrostatically separable substance through an exhaust passage,
An electrostatic separation means that introduces at least a part of a gas containing an electrostatically separable substance that is interposed in the exhaust passage and is discharged from the combustion device, and electrostatically separates the substance contained in the gas;
A first exhaust treatment means that is interposed in the exhaust passage on the downstream side of the electrostatic separation means and performs a predetermined treatment on the substance to be introduced;
An exhaust gas diversion passage for guiding at least a part of the gas containing the substance electrostatically separated by the electrostatic separation means to the first exhaust treatment means through a route different from the exhaust passage;
A second exhaust treatment means interposed in the exhaust shunt passage and performing a predetermined treatment on the substance to be introduced;
An exhaust treatment apparatus comprising:   The exhaust processing apparatus according to claim 1, wherein the predetermined processing in the first exhaust processing means is efficiently performed under conditions of a predetermined temperature or higher.   The predetermined process in the first exhaust treatment unit includes at least one of a process for purifying NOx or an oxidation process for a substance to be introduced. Exhaust treatment equipment.   The exhaust processing apparatus according to any one of claims 1 to 3, wherein the predetermined processing in the second exhaust processing means is efficiently performed under conditions of a predetermined temperature or higher.   The predetermined process in the second exhaust treatment unit includes at least one of a process for reducing NOx, an oxidation process for a substance to be introduced, or a reforming process for modifying a substance to be introduced. The exhaust treatment apparatus according to any one of claims 1 to 4, wherein the exhaust treatment apparatus is characterized.   A third exhaust treatment unit is provided which is interposed in the exhaust diversion passage on the downstream side or the upstream side of the second exhaust treatment unit and which performs a predetermined treatment on the introduced substance. The exhaust treatment device according to any one of claims 1 to 5.   The predetermined process in the third exhaust processing unit is a predetermined process different from that of the second exhaust unit, and the process is efficiently performed under a condition of a predetermined temperature or higher, or the temperature of the substance to be introduced is set. The exhaust treatment apparatus according to claim 6, comprising at least one of a process of raising or maintaining a predetermined temperature. The exhaust treatment apparatus according to any one of claims 1 to 7, wherein a flow rate control means for controlling a flow rate is disposed in the exhaust shunt passage.