JP2019190415A - Exhaust emission control device and vehicle - Google Patents

Exhaust emission control device and vehicle Download PDF

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JP2019190415A
JP2019190415A JP2018085986A JP2018085986A JP2019190415A JP 2019190415 A JP2019190415 A JP 2019190415A JP 2018085986 A JP2018085986 A JP 2018085986A JP 2018085986 A JP2018085986 A JP 2018085986A JP 2019190415 A JP2019190415 A JP 2019190415A
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exhaust gas
exhaust
turbine
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selective reduction
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朝幸 伊藤
Tomoyuki Ito
朝幸 伊藤
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Isuzu Motors Ltd
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    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A50/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE in human health protection, e.g. against extreme weather
    • Y02A50/20—Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/12—Improving ICE efficiencies

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Abstract

To provide an exhaust emission control device and a vehicle capable of preventing NOx in an exhaust gas from being discharged to atmospheric air even at a low temperature of the exhaust gas.SOLUTION: An exhaust emission control device includes an exhaust pipe in which an exhaust gas generated in an internal combustion engine flows, a turbine disposed in the exhaust pipe and constituting a part of a supercharger, a NOx selective reduction type catalyst disposed at a downstream side with respect to the turbine in an exhausting direction of the exhaust gas and enhancing reduction of nitrogen oxide in the exhaust gas in a case when a temperature of the exhaust gas is an active temperature, a bypass passage portion connecting a first region at an upstream side in the exhausting direction with respect to the turbine, and a second region between the turbine and the NOx selective reduction type catalyst in the exhaust pipe, an adjustment portion for adjusting a flow rate of the exhaust gas flowing in the bypass passage portion, and a reducer supply portion disposed on the bypass passage portion and supplying a reducer to reduce nitrogen oxide, to the exhaust gas flowing in the bypass passage portion.SELECTED DRAWING: Figure 1

Description

本開示は、排気浄化装置および車両に関する。   The present disclosure relates to an exhaust purification device and a vehicle.

従来、内燃機関の排気系において、排気管に設けられたタービンと、タービンの下流側に設けられた排気浄化触媒とを有する排気浄化装置が知られている。例えば、特許文献１には、排気管のタービンよりも上流側の部位と、タービンと排気浄化触媒との間の部位とを接続し、排気圧に応じて開閉するバイパス経路部が設けられた構成が開示されている。   Conventionally, in an exhaust system of an internal combustion engine, an exhaust purification device having a turbine provided in an exhaust pipe and an exhaust purification catalyst provided downstream of the turbine is known. For example, Patent Document 1 includes a bypass path portion that connects a portion of the exhaust pipe upstream of the turbine and a portion between the turbine and the exhaust purification catalyst, and opens and closes according to the exhaust pressure. Is disclosed.

また、排気浄化触媒として、内燃機関で生じた排気ガスに含まれる窒素酸化物（以下、「ＮＯｘ」という）を還元処理するＮＯｘ選択還元型触媒が知られている。ＮＯｘ選択還元型触媒は、排気管内に供給された前駆体（例えば、尿素水）から発生した還元剤（例えば、アンモニア）を吸着し、吸着したアンモニアにより排気ガスに含まれるＮＯｘを還元する。   As an exhaust purification catalyst, a NOx selective reduction type catalyst that performs a reduction treatment of nitrogen oxides (hereinafter referred to as “NOx”) contained in exhaust gas generated in an internal combustion engine is known. The NOx selective reduction catalyst adsorbs a reducing agent (for example, ammonia) generated from a precursor (for example, urea water) supplied into the exhaust pipe, and reduces the NOx contained in the exhaust gas by the adsorbed ammonia.

再表２０１０／０７３３５４号Table 2010/073354

しかしながら、例えば、内燃機関の冷間始動時においては、排気ガスの温度が、ＮＯｘ選択還元型触媒が活性化領域となる活性温度に達しない場合がある。特に、タービンを有する構成の場合、排熱エネルギーをタービンインペラの回転エネルギーに変換するため、タービンを通過した排気ガスの温度が低下し、排気ガスの温度がさらに昇温しにくい。そのため、ＮＯｘ選択還元型触媒において排気ガス中のＮＯｘを還元処理できず、当該ＮＯｘが大気に排出されるという問題が生じる。   However, for example, at the time of cold start of the internal combustion engine, the temperature of the exhaust gas may not reach the activation temperature at which the NOx selective reduction catalyst becomes the activation region. In particular, in the case of a configuration having a turbine, the exhaust heat energy is converted into the rotational energy of the turbine impeller, so the temperature of the exhaust gas that has passed through the turbine is lowered, and the temperature of the exhaust gas is more difficult to increase. Therefore, NOx in the exhaust gas cannot be reduced in the NOx selective reduction catalyst, and there arises a problem that the NOx is discharged to the atmosphere.

本開示の目的は、排気ガスの低温時においても、排気ガス中のＮＯｘが大気に排出されることを抑制することが可能な排気浄化装置および車両を提供することである。   An object of the present disclosure is to provide an exhaust emission control device and a vehicle that can prevent NOx in exhaust gas from being discharged into the atmosphere even when the exhaust gas is at a low temperature.

本開示に係る排気浄化装置は、
内燃機関で発生した排気ガスが流れる排気管と、
前記排気管に設けられ、過給機の一部を構成するタービンと、
前記排気ガスの排気方向における前記タービンよりも下流側に設けられ、前記排気ガスの温度が活性温度である場合に前記排気ガス中の窒素酸化物の還元を促進するＮＯｘ選択還元型触媒と、
前記排気管において、前記タービンよりも前記排気方向の上流側の第１部位と、前記タービンと前記ＮＯｘ選択還元型触媒との間の第２部位と、を接続するバイパス経路部と、
前記バイパス経路部に流れる前記排気ガスの流量を調整する調整部と、
前記排気ガスの温度に応じて、前記バイパス経路部に流れる前記排気ガスの流量を調整するように前記調整部を制御する制御部と、
を備える。 An exhaust emission control device according to the present disclosure includes:
An exhaust pipe through which exhaust gas generated in the internal combustion engine flows;
A turbine provided in the exhaust pipe and constituting a part of the supercharger;
A NOx selective reduction catalyst that is provided downstream of the turbine in the exhaust direction of the exhaust gas and promotes reduction of nitrogen oxides in the exhaust gas when the temperature of the exhaust gas is an active temperature;
In the exhaust pipe, a bypass path portion connecting a first part upstream of the turbine in the exhaust direction and a second part between the turbine and the NOx selective reduction catalyst;
An adjusting unit that adjusts the flow rate of the exhaust gas flowing through the bypass path unit;
A control unit that controls the adjusting unit to adjust the flow rate of the exhaust gas flowing through the bypass path unit according to the temperature of the exhaust gas;
Is provided.

本開示に係る車両は、
上記した排気浄化装置を備える。 The vehicle according to the present disclosure is
The above-described exhaust purification device is provided.

本開示によれば、排気ガスの低温時においても、排気ガス中のＮＯｘが大気に排出されることを抑制することができる。   According to the present disclosure, it is possible to suppress NOx in the exhaust gas from being discharged to the atmosphere even when the exhaust gas is at a low temperature.

本開示の実施の形態に係る排気浄化装置が適用された内燃機関の排気系を示す概略構成図である。1 is a schematic configuration diagram illustrating an exhaust system of an internal combustion engine to which an exhaust emission control device according to an embodiment of the present disclosure is applied. 排気浄化装置における調整制御の動作例を示すフローチャートである。It is a flowchart which shows the operation example of adjustment control in an exhaust gas purification apparatus. 変形例に係る排気浄化装置が適用された内燃機関の排気系を示す概略構成図である。It is a schematic block diagram which shows the exhaust system of the internal combustion engine to which the exhaust gas purification apparatus which concerns on a modification is applied.

以下、本開示の実施の形態を図面に基づいて詳細に説明する。図１は、本開示の実施の形態に係る排気浄化装置１００が適用された内燃機関１の排気系を示す概略構成図である。   Hereinafter, embodiments of the present disclosure will be described in detail based on the drawings. FIG. 1 is a schematic configuration diagram illustrating an exhaust system of an internal combustion engine 1 to which an exhaust purification device 100 according to an embodiment of the present disclosure is applied.

図１に示すように、内燃機関１は、車両Ｖに搭載される、例えばディーゼルエンジンであり、内燃機関１で生じた排気ガスを大気中に導くための排気浄化装置１００が設けられている。排気浄化装置１００は、排気管１１０と、タービン１２０と、バイパス経路部１３０と、調整部１４０と、温度検出部１５０と、制御部３００とを備えている。   As shown in FIG. 1, the internal combustion engine 1 is a diesel engine, for example, mounted on a vehicle V, and is provided with an exhaust purification device 100 for guiding exhaust gas generated in the internal combustion engine 1 into the atmosphere. The exhaust emission control device 100 includes an exhaust pipe 110, a turbine 120, a bypass path unit 130, an adjustment unit 140, a temperature detection unit 150, and a control unit 300.

排気管１１０では、内燃機関１から生じた排気ガスが流れる。排気管１１０には、排気ガスが流れる方向（図示左から右へ向かう方向、以下、「排気方向」という）の上流側から順に、タービン１２０、酸化触媒２１０、ＮＯｘ選択還元型触媒２２０、アンモニアスリップ触媒２３０等が設けられている。   In the exhaust pipe 110, exhaust gas generated from the internal combustion engine 1 flows. In the exhaust pipe 110, the turbine 120, the oxidation catalyst 210, the NOx selective reduction catalyst 220, the ammonia slip are sequentially arranged from the upstream side in the direction in which the exhaust gas flows (the direction from the left to the right in the drawing, hereinafter referred to as “exhaust direction”) A catalyst 230 and the like are provided.

酸化触媒２１０は、排気ガス中の一酸化窒素（ＮＯ）等を酸化させて二酸化窒素（ＮＯ２）を生成することで、ＮＯｘ選択還元型触媒２２０の浄化性能を向上させる。 The oxidation catalyst 210 improves the purification performance of the NOx selective reduction catalyst 220 by oxidizing nitrogen monoxide (NO) or the like in the exhaust gas to generate nitrogen dioxide (NO 2 ).

ＮＯｘ選択還元型触媒２２０は、排気管１１０における酸化触媒２１０の下流側に配置され、図示しない尿素水噴射部により噴射された尿素水に基づいて生成されたアンモニアを吸着する。ＮＯｘ選択還元型触媒２２０は、排気ガスの温度が活性温度のとき、吸着したアンモニアと、自身を通過する排気ガス中に含まれるＮＯｘとを反応させることで、当該ＮＯｘを還元する。活性温度は、ＮＯｘ選択還元型触媒２２０が活性化領域となる温度である。   The NOx selective reduction catalyst 220 is disposed downstream of the oxidation catalyst 210 in the exhaust pipe 110 and adsorbs ammonia generated based on urea water injected by a urea water injection unit (not shown). When the temperature of the exhaust gas is the activation temperature, the NOx selective reduction catalyst 220 reduces the NOx by causing the adsorbed ammonia to react with NOx contained in the exhaust gas passing through the NOx selective reduction catalyst 220. The activation temperature is a temperature at which the NOx selective reduction catalyst 220 becomes an activation region.

アンモニアスリップ触媒２３０は、排気方向におけるＮＯｘ選択還元型触媒２２０の下流側に位置しており、ＮＯｘ選択還元型触媒２２０で使用されず、スリップしたアンモニアを分解して、アンモニアが車両Ｖ外に排出されるのを防止する。なお、本実施の形態では、アンモニアスリップ触媒２３０は、排気管１１０において、ＮＯｘ選択還元型触媒２２０とは別のケースに収容されているが、本開示はこれに限定されず、ＮＯｘ選択還元型触媒２２０と同じケースに収容されていても良い。   The ammonia slip catalyst 230 is located downstream of the NOx selective reduction catalyst 220 in the exhaust direction and is not used by the NOx selective reduction catalyst 220, but decomposes the slipped ammonia and discharges the ammonia out of the vehicle V. To be prevented. In the present embodiment, the ammonia slip catalyst 230 is accommodated in a case different from the NOx selective reduction catalyst 220 in the exhaust pipe 110, but the present disclosure is not limited to this, and the NOx selective reduction type. It may be accommodated in the same case as the catalyst 220.

タービン１２０は、過給機の一部を構成しており、排気管１１０に設けられている。タービン１２０は、図示しないタービンインペラが、内燃機関１から排出された排気ガスにより回転する。また、タービン１２０は、過給機の他部を構成する、図示しない圧縮機と接続されている。圧縮機のコンプレッサインペラとタービンインペラとがシャフトにより一体に回転することで、吸気管から送り込まれる外気がコンプレッサインペラの回転により過給されて内燃機関１に送り込まれる。   The turbine 120 constitutes a part of the supercharger and is provided in the exhaust pipe 110. In the turbine 120, a turbine impeller (not shown) is rotated by exhaust gas discharged from the internal combustion engine 1. The turbine 120 is connected to a compressor (not shown) that constitutes the other part of the supercharger. When the compressor impeller and the turbine impeller of the compressor are integrally rotated by the shaft, the outside air sent from the intake pipe is supercharged by the rotation of the compressor impeller and sent to the internal combustion engine 1.

バイパス経路部１３０は、排気管１１０においてタービン１２０よりも排気方向の上流側の第１部位１１１と、タービン１２０とＮＯｘ選択還元型触媒２２０との間の第２部位１１２とを接続する。第２部位１１２は、排気管１１０における、酸化触媒２１０とＮＯｘ選択還元型触媒２２０との間の部位である。   The bypass passage unit 130 connects the first part 111 upstream of the turbine 120 in the exhaust pipe 110 in the exhaust direction and the second part 112 between the turbine 120 and the NOx selective reduction catalyst 220. The second portion 112 is a portion between the oxidation catalyst 210 and the NOx selective reduction catalyst 220 in the exhaust pipe 110.

調整部１４０は、バイパス経路部１３０に流れる排気ガスのバイパス流量を調整可能なバルブである。調整部１４０が制御部３００によって制御されることで、排気管１１０の排気ガスがバイパス経路部１３０に流れる。   The adjustment unit 140 is a valve capable of adjusting the bypass flow rate of the exhaust gas flowing through the bypass path unit 130. As the adjustment unit 140 is controlled by the control unit 300, the exhaust gas in the exhaust pipe 110 flows into the bypass path unit 130.

温度検出部１５０は、排気管１１０のタービン１２０と酸化触媒２１０との間の部位に設けられ、排気方向におけるＮＯｘ選択還元型触媒２２０よりも上流側の排気ガスの温度を検出する。   The temperature detector 150 is provided in a portion of the exhaust pipe 110 between the turbine 120 and the oxidation catalyst 210, and detects the temperature of the exhaust gas upstream of the NOx selective reduction catalyst 220 in the exhaust direction.

制御部３００は、例えば電子制御ユニットであり、図示しないＣＰＵ（Central Processing Unit）、ＲＯＭ（Read Only Memory）、ＲＡＭ（Random Access Memory）および入出力回路を備えている。制御部３００は、予め設定されたプログラムに基づいて、調整部１４０を介してバイパス経路部１３０に流れる排気ガスの流量を制御するように構成されている。   The control unit 300 is, for example, an electronic control unit, and includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and an input / output circuit (not shown). The control unit 300 is configured to control the flow rate of the exhaust gas flowing through the bypass path unit 130 via the adjustment unit 140 based on a preset program.

制御部３００は、温度検出部１５０により検出された排気ガスの温度に応じて、ＮＯｘ選択還元型触媒２２０におけるＮＯｘの還元処理が促進されるように調整部１４０を制御する。具体的には、制御部３００は、温度検出部１５０の検出結果に基づいて、排気ガスの温度が活性温度未満である場合、バイパス経路部１３０に排気ガスを流すように調整部１４０を制御する。なお、ここでいう「排気ガスの温度が活性温度未満である」とは、活性温度の範囲のうち、最低温度となる活性温度より低い温度のことをいう。   The control unit 300 controls the adjustment unit 140 so that the NOx reduction process in the NOx selective reduction catalyst 220 is promoted according to the temperature of the exhaust gas detected by the temperature detection unit 150. Specifically, based on the detection result of temperature detection unit 150, control unit 300 controls adjustment unit 140 so that the exhaust gas flows through bypass path unit 130 when the temperature of the exhaust gas is lower than the activation temperature. . Here, “the temperature of the exhaust gas is lower than the activation temperature” means a temperature lower than the activation temperature that is the lowest temperature in the range of the activation temperature.

排気ガスの温度が活性温度未満である場合、ＮＯｘ選択還元型触媒２２０における還元処理が行われにくいので、還元処理が行われなかったＮＯｘが大気に排出されやすくなる。特に、タービン１２０を有する構成の場合、タービン１２０を排気ガスが通過することで、排気ガスの排熱エネルギーがタービンインペラの回転エネルギーに変換されるので、排気ガスの温度が低下しやすい。   When the temperature of the exhaust gas is lower than the activation temperature, it is difficult to perform the reduction process in the NOx selective reduction catalyst 220, so that NOx that has not been subjected to the reduction process is easily discharged to the atmosphere. In particular, in the case of the configuration having the turbine 120, exhaust gas passes through the turbine 120, so that exhaust heat energy of the exhaust gas is converted into rotational energy of the turbine impeller, so that the temperature of the exhaust gas is likely to decrease.

そのため、本実施の形態では、制御部３００は、排気ガスの温度が活性温度未満である場合、バイパス経路部１３０に排気ガスを流すように調整部１４０を制御する。これにより、タービン１２０を通過していない、すなわち温度が低下していない排気ガスが直接的にＮＯｘ選択還元型触媒２２０に送り込まれる。この排気ガスはタービン１２０に起因する温度低下の影響を受けないので、当該排気ガスの熱をもって、ＮＯｘ選択還元型触媒２２０によるＮＯｘの還元処理が促進され、ひいてはＮＯｘが大気に排出されることを抑制することができる。   Therefore, in the present embodiment, the control unit 300 controls the adjustment unit 140 so that the exhaust gas flows through the bypass path unit 130 when the temperature of the exhaust gas is lower than the activation temperature. As a result, the exhaust gas that has not passed through the turbine 120, that is, the temperature of which has not decreased, is sent directly to the NOx selective reduction catalyst 220. Since this exhaust gas is not affected by the temperature decrease caused by the turbine 120, the heat of the exhaust gas promotes the NOx reduction process by the NOx selective reduction catalyst 220, and consequently NOx is discharged into the atmosphere. Can be suppressed.

また、制御部３００は、排気ガスの温度が活性温度以上である場合、バイパス経路部１３０に排気ガスを流さないように調整部１４０を制御する。排気ガスの温度が活性温度以上である場合、排気ガスの温度が十分に昇温した状態であるため、ＮＯｘ選択還元型触媒２２０にバイパス経路部１３０を介して排気ガスを送り込む必要がなくなる。そのため、上記のように制御することで、無駄にバイパス経路部１３０に排気ガスが流されることを抑制することができる。また、バイパス経路部１３０に排気ガスの一部が流れることによるタービン１２０の回転駆動力の低下を抑制することができる。   In addition, when the temperature of the exhaust gas is equal to or higher than the activation temperature, the control unit 300 controls the adjustment unit 140 so that the exhaust gas does not flow through the bypass path unit 130. When the temperature of the exhaust gas is equal to or higher than the activation temperature, the exhaust gas temperature is sufficiently raised, so that it is not necessary to send the exhaust gas to the NOx selective reduction catalyst 220 via the bypass passage 130. Therefore, by controlling as described above, it is possible to prevent the exhaust gas from flowing unnecessarily through the bypass path portion 130. In addition, it is possible to suppress a decrease in the rotational driving force of the turbine 120 due to a part of the exhaust gas flowing through the bypass path portion 130.

また、制御部３００は、バイパス経路部１３０に排気ガスを流す際、内燃機関１の動作状態に応じて、バイパス経路部１３０に排気ガスの一部を流し、かつ、タービン１２０に残りの排気ガスを流すように調整部１４０を制御する。このとき、制御部３００は、バイパス経路部１３０に流れる排気ガスの流量が、タービン１２０に流れる排気ガスの流量よりも多くなるように調整部１４０を制御する。   In addition, when the exhaust gas flows through the bypass passage portion 130, the control portion 300 causes a part of the exhaust gas to flow through the bypass passage portion 130 and the remaining exhaust gas to the turbine 120 according to the operating state of the internal combustion engine 1. The adjustment unit 140 is controlled to flow. At this time, the control unit 300 controls the adjustment unit 140 so that the flow rate of the exhaust gas flowing through the bypass path unit 130 is larger than the flow rate of the exhaust gas flowing through the turbine 120.

例えば、車両Ｖが走行しているとき、排気ガスの全部がバイパス経路部１３０に流れていると、タービン１２０側に排気ガスが送り込まれないので、過給機による過給が行われなくなる。そのため、このようなときには、バイパス経路部１３０に排気ガスの一部を流し、かつ、タービン１２０に残りの排気ガスを流すようにすることで、ＮＯｘ選択還元型触媒２２０を、タービン１２０を介さない排気ガスによって熱しつつ、タービン１２０のタービンインペラを回転させて過給機における過給を行わせることができる。   For example, when the vehicle V is traveling, if all of the exhaust gas flows into the bypass path portion 130, the exhaust gas is not sent to the turbine 120 side, so supercharging by the supercharger is not performed. Therefore, in such a case, a part of the exhaust gas flows through the bypass passage 130 and the remaining exhaust gas flows through the turbine 120, so that the NOx selective reduction catalyst 220 does not pass through the turbine 120. While being heated by the exhaust gas, the turbine impeller of the turbine 120 can be rotated to perform supercharging in the supercharger.

また、この場合、バイパス経路部１３０に流れる排気ガスの流量は、タービン１２０に流れる排気ガスの流量よりも多いので、ＮＯｘ選択還元型触媒２２０付近の温度を昇温させやすくし、ひいては還元処理の効率を向上させることができる。   In this case, the flow rate of the exhaust gas flowing through the bypass passage portion 130 is larger than the flow rate of the exhaust gas flowing through the turbine 120, so that the temperature in the vicinity of the NOx selective reduction catalyst 220 can be easily raised, and the reduction treatment is performed. Efficiency can be improved.

以上のように構成された排気浄化装置１００における調整制御の動作例について説明する。図２は、排気浄化装置１００における調整制御の動作例を示すフローチャートである。図２の処理は、例えば、車両Ｖの走行中において、適宜実行される。   An operation example of the adjustment control in the exhaust emission control device 100 configured as described above will be described. FIG. 2 is a flowchart showing an operation example of adjustment control in the exhaust purification apparatus 100. The process of FIG. 2 is appropriately executed while the vehicle V is traveling, for example.

図２に示すように、制御部３００は、排気ガスの温度が活性温度未満であるか否かについて判定する（ステップＳ１０１）。判定の結果、排気ガスの温度が活性温度以上である場合（ステップＳ１０１、ＮＯ）、処理はステップＳ１０４に遷移する。一方、排気ガスの温度が活性温度未満である場合（ステップＳ１０１、ＹＥＳ）、制御部３００は、排気ガスの一部をバイパス経路部１３０に流すように調整部１４０を制御する（ステップＳ１０２）。   As shown in FIG. 2, the controller 300 determines whether or not the temperature of the exhaust gas is lower than the activation temperature (step S101). As a result of the determination, when the temperature of the exhaust gas is equal to or higher than the activation temperature (step S101, NO), the process transitions to step S104. On the other hand, when the temperature of the exhaust gas is lower than the activation temperature (step S101, YES), the control unit 300 controls the adjustment unit 140 so that a part of the exhaust gas flows through the bypass path unit 130 (step S102).

次に、制御部３００は、排気ガスの温度が活性温度以上であるか否かについて判定する（ステップＳ１０３）。判定の結果、排気ガスの温度が活性温度未満である場合（ステップＳ１０３、ＮＯ）、ステップＳ１０３の処理が繰り返される。一方、排気ガスの温度が活性温度以上である場合（ステップＳ１０３、ＹＥＳ）、制御部３００は、排気ガスをバイパス経路部１３０に流さないように調整部１４０を制御する（ステップＳ１０４）。ステップＳ１０４の後、本制御は終了する。   Next, the control unit 300 determines whether or not the temperature of the exhaust gas is equal to or higher than the activation temperature (step S103). As a result of the determination, when the temperature of the exhaust gas is lower than the activation temperature (step S103, NO), the process of step S103 is repeated. On the other hand, when the temperature of the exhaust gas is equal to or higher than the activation temperature (step S103, YES), the control unit 300 controls the adjustment unit 140 so that the exhaust gas does not flow through the bypass path unit 130 (step S104). After step S104, this control ends.

以上のように構成された本実施の形態によれば、排気ガスの温度が活性温度未満である場合、排気ガスの一部がバイパス経路部１３０に流される。排気管１１０におけるタービン１２０側の経路では、タービン１２０を排気ガスが通過することで、排気ガスの排熱エネルギーがタービンインペラの回転エネルギーに変換されるので、排気ガスの温度が低下して活性温度まで上がりにくい。   According to the present embodiment configured as described above, when the temperature of the exhaust gas is lower than the activation temperature, a part of the exhaust gas is caused to flow through the bypass path portion 130. In the path on the turbine 120 side in the exhaust pipe 110, the exhaust gas passes through the turbine 120, so that the exhaust heat energy of the exhaust gas is converted into the rotational energy of the turbine impeller. Hard to go up.

そのため、ＮＯｘ選択還元型触媒２２０における還元処理が行われにくくなるが、本実施の形態では、そのようなとき、バイパス経路部１３０により、タービン１２０を通過する前の排気ガスがＮＯｘ選択還元型触媒２２０に送り込まれる。その結果、ＮＯｘ選択還元型触媒２２０付近が当該排気ガスによって昇温するので、ＮＯｘ選択還元型触媒２２０における還元処理が促進される。その結果、タービンによる排気ガスの温度低下に起因して、ＮＯｘが大気に排出されることを抑制することができる。   Therefore, the reduction process in the NOx selective reduction catalyst 220 is difficult to be performed, but in this embodiment, in such a case, the exhaust gas before passing through the turbine 120 is converted into the NOx selective reduction catalyst by the bypass passage unit 130 in such a case. 220 is sent. As a result, the temperature in the vicinity of the NOx selective reduction catalyst 220 is raised by the exhaust gas, so that the reduction process in the NOx selective reduction catalyst 220 is promoted. As a result, it is possible to suppress NOx from being discharged to the atmosphere due to the temperature decrease of the exhaust gas by the turbine.

ところで、タービン１２０の上流側で排気管１１０に接続されるバイパス経路部１３０に排気ガスを流す場合、全ての排気ガスをバイパス経路部１３０に流してしまうと、タービン１２０側に排気ガスが流れない。そのため、タービンインペラが排気ガスを利用して回転できないため、過給機における過給ができなくなるおそれがある。   By the way, when exhaust gas flows through the bypass path 130 connected to the exhaust pipe 110 on the upstream side of the turbine 120, if all exhaust gas flows through the bypass path 130, the exhaust gas does not flow to the turbine 120 side. . Therefore, since the turbine impeller cannot rotate using exhaust gas, there is a possibility that supercharging in the supercharger cannot be performed.

しかし、本実施の形態では、バイパス経路部１３０に排気ガスの一部を流し、タービン１２０側には、その残りの排気ガスを流すため、当該排気ガスによりタービン１２０のタービンインペラを回転させることができる。その結果、過給機によって過給させることができる。   However, in the present embodiment, a part of the exhaust gas flows through the bypass passage portion 130 and the remaining exhaust gas flows through the turbine 120 side. Therefore, the turbine impeller of the turbine 120 can be rotated by the exhaust gas. it can. As a result, it can be supercharged by the supercharger.

また、排気ガスの温度が活性温度未満のときにおける、バイパス経路部１３０における排気ガスの流量は、タービン１２０側に流れる排気ガスの流量よりも多い。このようにすることで、過給機における過給を行わせつつ、ＮＯｘ選択還元型触媒２２０付近の温度を効率よく昇温させることができる。   Further, when the temperature of the exhaust gas is lower than the activation temperature, the flow rate of the exhaust gas in the bypass passage 130 is larger than the flow rate of the exhaust gas flowing to the turbine 120 side. By doing in this way, the temperature in the vicinity of the NOx selective reduction catalyst 220 can be efficiently raised while performing supercharging in the supercharger.

なお、上記実施の形態では、温度検出部１５０によって排気ガスの温度を検出していたが、本開示はこれに限定されず、例えば、内燃機関１が始動してからの経過時間に基づいて排気ガスの温度を推定するようにしても良い。   In the embodiment described above, the temperature of the exhaust gas is detected by the temperature detection unit 150. However, the present disclosure is not limited to this, and for example, the exhaust gas is exhausted based on the elapsed time after the internal combustion engine 1 is started. The temperature of the gas may be estimated.

また、上記実施の形態では、バイパス経路部１３０が、排気管１１０の酸化触媒２１０とＮＯｘ選択還元型触媒２２０との間の部位に接続されていたが、本開示はこれに限定されない。例えば、図３に示すように、バイパス経路部１３０が、排気管１１０のタービン１２０と酸化触媒２１０との間の部位に接続されていても良い。ただし、酸化触媒２１０を排気ガスが通過することで多少排気ガスの温度が低下することが考えられるので、ＮＯｘ選択還元型触媒２２０における還元処理促進の観点から、バイパス経路部１３０から直接排気ガスがＮＯｘ選択還元型触媒２２０に供給される図１の構成であることが好ましい。   In the above embodiment, the bypass passage 130 is connected to the site between the oxidation catalyst 210 and the NOx selective reduction catalyst 220 of the exhaust pipe 110, but the present disclosure is not limited to this. For example, as shown in FIG. 3, the bypass passage portion 130 may be connected to a portion of the exhaust pipe 110 between the turbine 120 and the oxidation catalyst 210. However, since it is considered that the temperature of the exhaust gas slightly decreases as the exhaust gas passes through the oxidation catalyst 210, the exhaust gas directly flows from the bypass passage 130 from the viewpoint of promoting the reduction process in the NOx selective reduction catalyst 220. 1 is preferably supplied to the NOx selective reduction catalyst 220.

また、上記実施の形態では、排気ガスの一部をバイパス経路部１３０に流していたが、本開示はこれに限定されず、例えば、アイドリング時のような過給機における過給が必要ないようなとき等、必要に応じて排気ガスの全部をバイパス経路部１３０に流すようにしても良い。   Further, in the above-described embodiment, a part of the exhaust gas is allowed to flow to the bypass passage portion 130. However, the present disclosure is not limited to this, and for example, supercharging in the supercharger at the time of idling is not necessary. When necessary, all of the exhaust gas may be allowed to flow through the bypass passage portion 130 as necessary.

また、上記実施の形態における排気浄化装置１００は、ディーゼルエンジンを搭載した車両Ｖに搭載されていたが、本開示はこれに限定されず、例えば、ガソリンエンジンを搭載した車両に搭載されていても良い。   Moreover, although the exhaust emission control device 100 in the above embodiment is mounted on the vehicle V equipped with a diesel engine, the present disclosure is not limited to this, and may be mounted on a vehicle equipped with a gasoline engine, for example. good.

その他、上記実施の形態は、何れも本開示を実施するにあたっての具体化の一例を示したものに過ぎず、これらによって本開示の技術的範囲が限定的に解釈されてはならないものである。すなわち、本開示はその要旨、またはその主要な特徴から逸脱することなく、様々な形で実施することができる。   In addition, each of the above-described embodiments is merely an example of implementation in carrying out the present disclosure, and the technical scope of the present disclosure should not be construed in a limited manner. That is, the present disclosure can be implemented in various forms without departing from the gist or the main features thereof.

本開示の排気浄化装置は、排気ガスの低温時においても、排気ガス中のＮＯｘが大気に排出されることを抑制することが可能な排気浄化装置および車両として有用である。   The exhaust purification device of the present disclosure is useful as an exhaust purification device and a vehicle that can suppress NOx in the exhaust gas from being discharged into the atmosphere even at a low temperature of the exhaust gas.

１ 内燃機関
１００ 排気浄化装置
１１０ 排気管
１２０ タービン
１３０ バイパス経路部
１４０ 調整部
１５０ 温度検出部
２１０ 酸化触媒
２２０ ＮＯｘ選択還元型触媒
２３０ アンモニアスリップ触媒
３００ 制御部
Ｖ 車両 DESCRIPTION OF SYMBOLS 1 Internal combustion engine 100 Exhaust gas purification device 110 Exhaust pipe 120 Turbine 130 Bypass path part 140 Adjustment part 150 Temperature detection part 210 Oxidation catalyst 220 NOx selective reduction type catalyst 230 Ammonia slip catalyst 300 Control part V Vehicle

Claims (6)

内燃機関で発生した排気ガスが流れる排気管と、
前記排気管に設けられ、過給機の一部を構成するタービンと、
前記排気ガスの排気方向における前記タービンよりも下流側に設けられ、前記排気ガスの温度が活性温度である場合に、前記排気ガス中の窒素酸化物の還元を促進するＮＯｘ選択還元型触媒と、
前記排気管において、前記タービンよりも前記排気方向の上流側の第１部位と、前記タービンと前記ＮＯｘ選択還元型触媒との間の第２部位と、を接続するバイパス経路部と、
前記バイパス経路部に流れる前記排気ガスの流量を調整する調整部と、
前記バイパス経路部に設けられ、前記バイパス経路部を流れる前記排気ガスに前記窒素酸化物を還元する還元剤を供給する還元剤供給部と、
を備える排気浄化装置。 An exhaust pipe through which exhaust gas generated in the internal combustion engine flows;
A turbine provided in the exhaust pipe and constituting a part of the supercharger;
A NOx selective reduction catalyst that is provided downstream of the turbine in the exhaust direction of the exhaust gas and promotes reduction of nitrogen oxides in the exhaust gas when the temperature of the exhaust gas is an activation temperature;
In the exhaust pipe, a bypass path portion connecting a first part upstream of the turbine in the exhaust direction and a second part between the turbine and the NOx selective reduction catalyst;
An adjusting unit that adjusts the flow rate of the exhaust gas flowing through the bypass path unit;
A reducing agent supply unit that is provided in the bypass path part and supplies a reducing agent that reduces the nitrogen oxides to the exhaust gas flowing through the bypass path part;
An exhaust purification device comprising: 前記還元剤供給部の位置は、前記バイパス経路部における、前記第２部位よりも前記第１部位に近い位置である、
請求項１に記載の排気浄化装置。 The position of the reducing agent supply unit is a position closer to the first part than the second part in the bypass path part.
The exhaust emission control device according to claim 1. 前記排気ガスの温度が前記活性温度未満である場合、前記バイパス経路部に前記排気ガスが流れるように前記調整部を制御する制御部を備える、
請求項１または請求項２に記載の排気浄化装置。 When the temperature of the exhaust gas is lower than the activation temperature, the controller includes a control unit that controls the adjustment unit so that the exhaust gas flows through the bypass path unit.
The exhaust emission control device according to claim 1 or 2. 前記制御部は、前記ＮＯｘ選択還元型触媒における前記還元剤の吸着量に応じて前記還元剤供給部を制御する、
請求項３に記載の排気浄化装置。 The control unit controls the reducing agent supply unit according to the amount of adsorption of the reducing agent in the NOx selective reduction catalyst.
The exhaust emission control device according to claim 3. 前記排気管において前記タービンと前記ＮＯｘ選択還元型触媒との間に設けられる酸化触媒を備え、
前記第２部位は、前記酸化触媒と前記ＮＯｘ選択還元型触媒との間の部位である、
請求項１〜４の何れか１項に記載の排気浄化装置。 An oxidation catalyst provided between the turbine and the NOx selective reduction catalyst in the exhaust pipe;
The second part is a part between the oxidation catalyst and the NOx selective reduction catalyst.
The exhaust emission control device according to any one of claims 1 to 4. 請求項１〜５の何れか１項に記載の排気浄化装置を備える、
車両。
The exhaust emission control device according to any one of claims 1 to 5 is provided.
vehicle.
JP2018085986A 2018-04-27 2018-04-27 Exhaust emission control device and vehicle Pending JP2019190415A (en)

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013002355A (en) * 2011-06-16 2013-01-07 Ihi Corp Denitration device
JP2013204547A (en) * 2012-03-29 2013-10-07 Man Diesel & Turbo Se Internal combustion engine
US20140223902A1 (en) * 2013-02-13 2014-08-14 Ford Global Technologies, Llc Internal combustion engine with selective catalytic converter for the reduction of nitrogen oxides and method for operating an internal combustion engine of said type
JP2017122391A (en) * 2016-01-06 2017-07-13 株式会社Ｓｏｋｅｎ Exhaust emission control device for internal combustion engine
JP2017218917A (en) * 2016-06-03 2017-12-14 トヨタ自動車株式会社 Exhaust emission control system for internal combustion engine

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013002355A (en) * 2011-06-16 2013-01-07 Ihi Corp Denitration device
JP2013204547A (en) * 2012-03-29 2013-10-07 Man Diesel & Turbo Se Internal combustion engine
US20140223902A1 (en) * 2013-02-13 2014-08-14 Ford Global Technologies, Llc Internal combustion engine with selective catalytic converter for the reduction of nitrogen oxides and method for operating an internal combustion engine of said type
JP2017122391A (en) * 2016-01-06 2017-07-13 株式会社Ｓｏｋｅｎ Exhaust emission control device for internal combustion engine
JP2017218917A (en) * 2016-06-03 2017-12-14 トヨタ自動車株式会社 Exhaust emission control system for internal combustion engine

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