[go: up one dir, main page]

JP2008075610A - Exhaust treatment device - Google Patents

Exhaust treatment device Download PDF

Info

Publication number
JP2008075610A
JP2008075610A JP2006258145A JP2006258145A JP2008075610A JP 2008075610 A JP2008075610 A JP 2008075610A JP 2006258145 A JP2006258145 A JP 2006258145A JP 2006258145 A JP2006258145 A JP 2006258145A JP 2008075610 A JP2008075610 A JP 2008075610A
Authority
JP
Japan
Prior art keywords
exhaust
nox
catalyst
fuel
exhaust gas
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP2006258145A
Other languages
Japanese (ja)
Inventor
Hiroshi Hirabayashi
浩 平林
Mitsuru Hosoya
満 細谷
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hino Motors Ltd
Original Assignee
Hino Motors Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hino Motors Ltd filed Critical Hino Motors Ltd
Priority to JP2006258145A priority Critical patent/JP2008075610A/en
Publication of JP2008075610A publication Critical patent/JP2008075610A/en
Pending legal-status Critical Current

Links

Classifications

    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02TCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00Road transport of goods or passengers
    • Y02T10/10Internal combustion engine [ICE] based vehicles
    • Y02T10/12Improving ICE efficiencies

Landscapes

  • Exhaust Gas After Treatment (AREA)

Abstract

<P>PROBLEM TO BE SOLVED: To provide an exhaust gas treating device capable of efficiently conducting a removal treatment of NOx by effectively exercising NOx reduction action of a hydrocarbon selective reduction type NOx catalyst. <P>SOLUTION: In the exhaust gas treating device 30, an oxidation catalyst 40, an HC-SCR catalyst 50, a catalyzed diesel particulate filter 60 are provided in this order from an exhaust gas upstream side and a fuel addition device 70 capable of adding and supplying a fuel (HC) to exhaust gas is provided between the oxidation catalyst 40 and the HC-SCR catalyst 50. With this arrangement, NOx reduction action of the HC-SCR catalyst 50 is efficiently exercised and the exhaust quantity of NOx can be effectively reduced by adding and supplying the fuel to the exhaust gas containing NO<SB>2</SB>with oxidative effect of the oxidation catalyst 40. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

本発明は、燃焼装置から排出され種々の排出物質を含む気体(排気)を処理する排気処理装置に関する。   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.

燃焼装置からの排気を浄化して大気汚染の拡大を抑制することは重要な課題であるが、特許文献1に記載されるように、例えば、ディーゼル機関において、排気が導かれる排気通路の途中に、酸素共存下でも選択的にNOx(窒素酸化物)をHC(炭化水素)と反応させ得るよう反応選択性を高めたHC(炭化水素)選択還元型NOx触媒{HC−SCR(HC−Selective Catalytic Reduction)方式の触媒(以下、HC−SCR触媒とも言う)}を介装し、該HC選択還元型NOx触媒の排気上流側に必要量のHCを添加して該HCをHC選択還元型NOx触媒上で排気中のNOxと還元反応させ、これによりNOxの排出量の低減を図るようにしたものがある。   Although it is an important issue to purify the exhaust from the combustion device and suppress the expansion of air pollution, as described in Patent Document 1, for example, in a diesel engine, in the middle of an exhaust passage through which exhaust is guided HC (hydrocarbon) selective reduction type NOx catalyst having improved reaction selectivity so that NOx (nitrogen oxide) can selectively react with HC (hydrocarbon) even in the presence of oxygen {HC-SCR (HC-Selective Catalytic) Reduction type catalyst (hereinafter also referred to as HC-SCR catalyst)}, a required amount of HC is added to the exhaust upstream side of the HC selective reduction type NOx catalyst, and the HC is reduced to the HC selective reduction type NOx catalyst. In some cases, a reduction reaction with NOx in the exhaust gas is performed to reduce the NOx emission amount.

また、例えば、HC選択還元型NOx触媒を利用した、次のような排気処理装置も提案されている。このものは、図6に示すように、ディーゼル機関1から排出された排気が、排気通路2を介して排気処理装置3に導かれる。前記排気処理装置3には、排気上流側から、HC−SCR触媒5、酸化触媒4、触媒化ディーゼルパティキュレートフィルタ6が、この順番で配設されると共に、前記HC−SCR触媒5の排気上流側に、排気に対して燃料を添加供給するための燃料添加装置7が介装されている。   Further, for example, the following exhaust treatment device using an HC selective reduction type NOx catalyst has been proposed. In this apparatus, as shown in FIG. 6, the exhaust discharged from the diesel engine 1 is guided to the exhaust treatment device 3 through the exhaust passage 2. In the exhaust treatment device 3, an HC-SCR catalyst 5, an oxidation catalyst 4, and a catalyzed diesel particulate filter 6 are disposed in this order from the exhaust upstream side, and the exhaust upstream of the HC-SCR catalyst 5 is disposed. On the side, a fuel addition device 7 for adding and supplying fuel to the exhaust is interposed.

ここで、前記燃料添加装置7は、燃料タンク7Cに収容される燃料(HC)を燃料加圧ポンプ7Bを介して燃料添加ノズル7Aに給送し、該燃料添加ノズル7Aは排気通路2を流れる排気に対して燃料(HC)を添加供給し、前記HC−SCR触媒5において、前記燃料添加と排気中のNOxとを反応させて、NOxの浄化を図る。   Here, the fuel addition device 7 feeds the fuel (HC) stored in the fuel tank 7C to the fuel addition nozzle 7A via the fuel pressurizing pump 7B, and the fuel addition nozzle 7A flows through the exhaust passage 2. Fuel (HC) is added and supplied to the exhaust, and the HC-SCR catalyst 5 reacts the fuel addition with NOx in the exhaust to purify NOx.

そして、その排気下流側において、酸化触媒4で排気中のHC、CO等を酸化除去すると共に、PMを触媒化ディーゼルパティキュレートフィルタ6で捕集して排気中からPMを除去することで、排気に含まれる各種の有害物質の大気中への排出を抑制している。   Then, on the downstream side of the exhaust gas, the oxidation catalyst 4 oxidizes and removes HC, CO, etc., and PM is collected by the catalyzed diesel particulate filter 6 to remove PM from the exhaust gas. Controls the release of various harmful substances contained in the atmosphere.

なお、触媒化ディーゼルパティキュレートフィルタ6は、排気中のPM(パティキュレートマター:粒子状物質=主に黒煙(スス)、SOFと称される燃え残った燃料や潤滑油の成分、サルフェートと称される軽油燃料中の硫黄分から生成される成分を含む)の大気への排出を抑えるために排気中のPMを捕集するためのディーゼルパティキュレートフィルタであって、当該ディーゼルパティキュレートフィルタを酸化触媒の反応熱を利用して良好に再生可能にするために酸化触媒を一体的に担持させたディーゼルパティキュレートフィルタである。
特開2004−204700号公報
The catalyzed diesel particulate filter 6 is called PM (particulate matter: particulate matter = mainly black smoke (soot), unburned fuel called SOF, a component of lubricating oil, or sulfate). A diesel particulate filter for collecting PM in the exhaust gas in order to suppress emission to the atmosphere (including components generated from sulfur content in the light oil fuel), the diesel particulate filter being an oxidation catalyst This is a diesel particulate filter in which an oxidation catalyst is integrally supported so that it can be regenerated satisfactorily using the heat of reaction.
JP 2004-204700 A

本発明者等は、種々の実験研究を重ねるうちに、特許文献1に記載のものや、図6に示したものでは、前記HC−SCR触媒5の有するNOx還元作用を有効に利用できていないことを解明する一方、かかる解明の結果に基づいて前記HC−SCR触媒5のNOx還元作用をより効率良く発揮させることができる手法を見出した。   The inventors have not been able to effectively utilize the NOx reduction action of the HC-SCR catalyst 5 in the one described in Patent Document 1 or the one shown in FIG. On the other hand, on the basis of the results of such elucidation, a technique has been found that allows the HC-SCR catalyst 5 to exhibit the NOx reduction action more efficiently.

本発明は、かかる実情に鑑みなされたもので、炭化水素(HC)選択還元型NOx触媒のNOx還元作用を有効に発揮させNOxの浄化処理を効率的に行うことができる排気処理装置を提供することを目的とする。   The present invention has been made in view of such a situation, and provides an exhaust treatment device that can effectively perform a NOx purification process by effectively exhibiting a NOx reduction action of a hydrocarbon (HC) selective reduction type NOx catalyst. For the purpose.

本発明に係る排気処理装置は、
燃焼装置から排気通路を介して排出される排気を処理する排気処理装置であって、
排気中の所定の成分に対して酸化処理を施すための酸化触媒と、
排気通路に炭化水素を供給する炭化水素供給手段と、
NOxを炭化水素と反応させ得るよう反応選択性を高めた炭化水素選択還元型NOx触媒と、
が、排気下流側に向けて、この順番で前記排気通路に介装されることを特徴とする。
An exhaust treatment apparatus according to the present invention includes:
An exhaust treatment device for treating exhaust gas discharged from a combustion device through an exhaust passage,
An oxidation catalyst for subjecting predetermined components in the exhaust to oxidation treatment;
Hydrocarbon supply means for supplying hydrocarbons to the exhaust passage;
A hydrocarbon selective reduction type NOx catalyst having enhanced reaction selectivity so that NOx can be reacted with a hydrocarbon;
Are arranged in the exhaust passage in this order toward the exhaust downstream side.

また、本発明に係る排気処理装置は、前記炭化水素供給手段と、前記HC選択還元型NOx触媒と、の間に、前記炭化水素供給手段から供給された炭化水素と、前記排気通路を流れる排気と、を混合するための混合手段が介装されることができる。   Further, the exhaust treatment apparatus according to the present invention includes a hydrocarbon supplied from the hydrocarbon supply unit and an exhaust gas flowing through the exhaust passage between the hydrocarbon supply unit and the HC selective reduction type NOx catalyst. And a mixing means for mixing.

なお、本発明に係る排気処理装置は、前記排気通路内のパティキュレートマターを捕集するディーゼルパティキュレートフィルタが、前記炭化水素選択還元型NOx触媒の排気下流側において、前記排気通路に介装されることができる。   In the exhaust treatment device according to the present invention, a diesel particulate filter that collects particulate matter in the exhaust passage is interposed in the exhaust passage on the exhaust downstream side of the hydrocarbon selective reduction type NOx catalyst. Can.

本発明によれば、HC選択還元型NOx触媒のNOx還元作用を有効に発揮させ、NOxの浄化処理を効率的に行うことができる排気処理装置を提供することができる。   ADVANTAGE OF THE INVENTION According to this invention, the exhaust-gas treatment apparatus which can exhibit the NOx reduction effect | action of a HC selective reduction type NOx catalyst effectively, and can perform the purification process of NOx efficiently can be provided.

以下、本発明に係る実施の形態を、添付の図面を参照しつつ説明する。なお、以下で説明する実施の形態により、本発明が限定されるものではない。   DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments according to the present invention will be described with reference to the accompanying drawings. The present invention is not limited to the embodiments described below.

図1に示すように、本発明の第1の実施の形態では、内燃機関10から排出された排気が排気通路20を介して排気処理装置30に導かれる。なお、内燃機関10は、例えばディーゼル燃焼を行うディーゼルエンジンとすることができるが、これに限定されるものではなく、排気を伴う燃焼装置であれば、ガソリンエンジンその他の内燃機関の他、外燃機関とすることもでき、燃焼方式に拘わらず、あらゆる移動式・定置式の燃焼装置とすることができる。   As shown in FIG. 1, in the first embodiment of the present invention, the exhaust discharged from the internal combustion engine 10 is guided to the exhaust treatment device 30 via the exhaust passage 20. The internal combustion engine 10 can be, for example, a diesel engine that performs diesel combustion. However, the present invention is not limited to this, and any internal combustion engine other than a gasoline engine or other internal combustion engine may be used as long as it is a combustion apparatus that includes exhaust gas. It can also be an engine, and can be any mobile or stationary combustion device regardless of the combustion method.

前記排気処理装置30には、排気上流側から、酸化触媒40、HC−SCR触媒50、触媒化ディーゼルパティキュレートフィルタ60が、この順番で配設されると共に、前記酸化触媒40と前記HC−SCR触媒50との間に、排気に対して燃料(HC)を添加供給可能な燃料添加装置70が介装されている。   The exhaust treatment device 30 is provided with an oxidation catalyst 40, an HC-SCR catalyst 50, and a catalyzed diesel particulate filter 60 in this order from the exhaust upstream side, and the oxidation catalyst 40 and the HC-SCR. A fuel addition device 70 capable of adding and supplying fuel (HC) to the exhaust is interposed between the catalyst 50 and the catalyst 50.

前記酸化触媒40は、内燃機関10から排出される排気中のNOを酸化してNOに変換する。また、排気中のHC、CO等を酸化してこれらを浄化する。 The oxidation catalyst 40 is converted to NO 2 by oxidizing NO in the exhaust gas discharged from the internal combustion engine 10. Also, HC, CO, etc. in the exhaust are oxidized to purify them.

前記燃料添加装置70は、本発明に係る炭化水素供給手段に相当し、燃料タンク73に収容される燃料(軽油その他の燃料であって良い)を燃料ポンプ72により、前記酸化触媒40と前記HC−SCR触媒50との間の排気通路に臨んで設けられる燃料添加ノズル71に給送し、該燃料添加ノズル71は前記酸化触媒40を通過した排気に対して燃料(HC)を噴射供給する。   The fuel addition device 70 corresponds to the hydrocarbon supply means according to the present invention, and the fuel (which may be light oil or other fuel) accommodated in the fuel tank 73 is fed by the fuel pump 72 to the oxidation catalyst 40 and the HC. -It feeds to the fuel addition nozzle 71 provided facing the exhaust passage with the SCR catalyst 50, and the fuel addition nozzle 71 injects and supplies fuel (HC) to the exhaust gas that has passed through the oxidation catalyst 40.

前記HC−SCR触媒50では、前記燃料添加ノズル71を介して添加供給された燃料と、排気中のNOxと、を反応させて、NOxを還元し浄化する。   In the HC-SCR catalyst 50, the fuel added and supplied via the fuel addition nozzle 71 reacts with NOx in the exhaust to reduce and purify NOx.

ここにおいて、本発明者等は次のことを解明した。
すなわち、図6に示した従来の排気処理装置のように、排気上流側から、HC−SCR触媒5、酸化触媒4、触媒化ディーゼルパティキュレートフィルタ6の順番で配設し、前記HC−SCR触媒5の排気上流側に燃料を添加するように構成した場合、ディーゼルエンジンから排出された直後の排気中にはNOやNOx(ここでは、NO以外のNOx)が多く存在するため、HC−SCR触媒5でのNOxの還元反応の効率が悪く、NOxの排出量を効果的に低減できていなかった。
Here, the present inventors have elucidated the following.
That is, like the conventional exhaust treatment apparatus shown in FIG. 6, the HC-SCR catalyst 5, the oxidation catalyst 4, and the catalyzed diesel particulate filter 6 are arranged in this order from the exhaust upstream side, and the HC-SCR catalyst is arranged. When the fuel is added to the upstream side of the exhaust gas 5, since there is a lot of NO and NOx (here, NOx other than NO 2 ) in the exhaust immediately after being discharged from the diesel engine, the HC-SCR The efficiency of the NOx reduction reaction at the catalyst 5 was poor, and the amount of NOx emissions could not be reduced effectively.

一般に、HC−SCR触媒は、NOx+HC→N+CO+HOなるNOx還元作用を奏するが、排気中のNOxとして、NOが多く存在する場合の方が、NOやNO以外のNOxが多く存在する場合に比べて、より効率良く上記NOx還元作用を奏することができる。 In general, the HC-SCR catalyst has a NOx reduction action of NOx + HC → N 2 + CO 2 + H 2 O. However, when NO 2 is present in a large amount as NOx in the exhaust, NOx other than NO or NO 2 is present. The NOx reduction action can be achieved more efficiently than in the case where there are many.

このため、図6に示した従来の排気処理装置のように、内燃機関1から排出された直後のNOやNOx(ここでは、NO以外のNOx)が多く存在する排気に対して燃料(HC)を供給し、HC−SCR触媒5によるNOx還元反応を行わせていたのでは、NOxの還元反応の効率が悪く、NOxの排出量を効果的に低減することができない。 For this reason, as in the conventional exhaust treatment apparatus shown in FIG. 6, fuel (HC) is produced against exhaust gas that contains a large amount of NO or NOx (here, NOx other than NO 2 ) immediately after being discharged from the internal combustion engine 1. ) And the NOx reduction reaction by the HC-SCR catalyst 5 is performed, the efficiency of the NOx reduction reaction is poor, and the NOx emission amount cannot be effectively reduced.

そこで、本実施の形態では、図1に示したように、HC−SCR触媒50の排気上流側に、前記酸化触媒40を配設すると共に、該酸化触媒40と前記HC−SCR触媒50との間に前記燃料添加ノズル71を配設し、前記酸化触媒40の酸化作用を受けてNOが多く存在する排気に対して燃料(HC)を添加供給することで、前記HC−SCR触媒50のNOx還元作用を効率良く行わせ、以ってNOxの排出量の効果的な低減を図っている。 Therefore, in the present embodiment, as shown in FIG. 1, the oxidation catalyst 40 is disposed on the exhaust upstream side of the HC-SCR catalyst 50, and the oxidation catalyst 40 and the HC-SCR catalyst 50 are The fuel addition nozzle 71 is disposed in between, and the fuel (HC) is added and supplied to the exhaust gas in which a large amount of NO 2 exists due to the oxidation action of the oxidation catalyst 40, so that the HC-SCR catalyst 50 The NOx reduction action is efficiently performed, thereby effectively reducing the NOx emission amount.

なお、本実施の形態では、前記HC−SCR触媒50の排気下流側において、PMを触媒化ディーゼルパティキュレートフィルタ60で捕集して排気中からPMを除去することで、排気中の各種の有害物質の大気中への排出を抑制している。   In the present embodiment, on the exhaust downstream side of the HC-SCR catalyst 50, PM is collected by the catalyzed diesel particulate filter 60 and removed from the exhaust gas, thereby causing various harmful effects in the exhaust gas. Controls the release of substances into the atmosphere.

ところで、触媒化ディーゼルパティキュレートフィルタ60は、排気中のPM(パティキュレートマター:粒子状物質=主に黒煙(スス)、SOFと称される燃え残った燃料や潤滑油の成分、サルフェートと称される軽油燃料中の硫黄分から生成される成分を含む)の大気への排出を抑えるために排気中のPMを捕集するためのディーゼルパティキュレートフィルタであって、当該ディーゼルパティキュレートフィルタを酸化触媒の反応熱を利用して良好に再生可能にするために酸化触媒を一体的に担持させたディーゼルパティキュレートフィルタである。   By the way, the catalyzed diesel particulate filter 60 is called PM (particulate matter: particulate matter = mainly black smoke (soot), unburned fuel called SOF, component of lubricating oil, and sulfate) in exhaust gas. A diesel particulate filter for collecting PM in the exhaust gas in order to suppress emission to the atmosphere (including components generated from sulfur content in the light oil fuel), the diesel particulate filter being an oxidation catalyst This is a diesel particulate filter in which an oxidation catalyst is integrally supported so that it can be regenerated satisfactorily using the heat of reaction.

ここで、本実施の形態に係る排気処理装置30を用いた場合のNOx低減率と、図6に示した従来の排気処理装置3を用いた場合のNOx低減率と、を都市内走行モード(JE05モード)において比較した結果を、図2に示す。当該図2から理解されるように、従来の排気処理装置3のNOx低減率は22%であったが、本実施の形態に係る排気処理装置30を用いれば、NOx低減率を31%まで向上させることができる。   Here, the NOx reduction rate when the exhaust treatment device 30 according to the present embodiment is used and the NOx reduction rate when the conventional exhaust treatment device 3 shown in FIG. FIG. 2 shows the result of comparison in (JE05 mode). As understood from FIG. 2, the NOx reduction rate of the conventional exhaust treatment device 3 was 22%. However, if the exhaust treatment device 30 according to the present embodiment is used, the NOx reduction rate is improved to 31%. Can be made.

次に、本発明の第2の実施の形態について説明する。なお、第1の実施の形態と同様の要素には同一の符号を付すこととして詳細な説明は省略する。   Next, a second embodiment of the present invention will be described. In addition, detailed description is abbreviate | omitted as the same code | symbol is attached | subjected to the element similar to 1st Embodiment.

第2の実施の形態では、図3に示すように、内燃機関10から排出された排気が排気通路20を介して排気処理装置300に導かれる。   In the second embodiment, as shown in FIG. 3, the exhaust discharged from the internal combustion engine 10 is guided to the exhaust treatment device 300 via the exhaust passage 20.

前記排気処理装置300には、排気上流側から、酸化触媒40、ミキサー400、HC−SCR触媒50、触媒化ディーゼルパティキュレートフィルタ60が、この順番で配設されると共に、前記酸化触媒40と前記ミキサー400との間に、排気に対して燃料を添加供給するための燃料添加装置70が介装されている。   The exhaust treatment apparatus 300 is provided with an oxidation catalyst 40, a mixer 400, an HC-SCR catalyst 50, and a catalyzed diesel particulate filter 60 in this order from the exhaust upstream side, and the oxidation catalyst 40 and the Between the mixer 400, a fuel addition device 70 for adding and supplying fuel to the exhaust is interposed.

前記酸化触媒40では、内燃機関10から排出される排気中のNOを酸化してNOに変換する。また、排気中のHC、CO等を酸化してこれらを浄化する。 The oxidation catalyst 40 oxidizes NO in the exhaust discharged from the internal combustion engine 10 and converts it into NO 2 . Also, HC, CO, etc. in the exhaust are oxidized to purify them.

そして、前記燃料添加装置70の燃料添加ノズル71は、前記酸化触媒40を通過した排気に対して燃料(HC)を噴射供給する。   The fuel addition nozzle 71 of the fuel addition device 70 injects and supplies fuel (HC) to the exhaust gas that has passed through the oxidation catalyst 40.

前記HC−SCR触媒50では、前記燃料添加ノズル71を介して添加供給された燃料(HC)と排気中のNOxとを反応させて、NOxを還元し浄化する。   In the HC-SCR catalyst 50, the fuel (HC) added and supplied via the fuel addition nozzle 71 reacts with NOx in the exhaust to reduce and purify NOx.

ここにおいて、第2の実施の形態においても、第1の実施の形態において説明したと同様、図6に示した従来の排気処理装置のように、排気上流側から、HC−SCR触媒5、酸化触媒4、触媒化ディーゼルパティキュレートフィルタ6の順番で配設し、前記HC−SCR触媒5の排気上流側に燃料を添加するように構成した場合に、ディーゼルエンジンから排出された直後の排気中にはNOやNOx(ここでは、NO以外のNOx)が多く存在し、HC−SCR触媒5でのNOxの還元反応の効率が低く、NOxの排出量を効果的に低減できない、という状態を回避する。 Here, in the second embodiment as well, as described in the first embodiment, the HC-SCR catalyst 5 and the oxidation are formed from the exhaust upstream side as in the conventional exhaust treatment apparatus shown in FIG. When the catalyst 4 and the catalyzed diesel particulate filter 6 are arranged in this order and fuel is added to the exhaust upstream side of the HC-SCR catalyst 5, the exhaust gas immediately after being discharged from the diesel engine nO and NOx (in this case, nO 2 other than NOx) have many present and low efficiency of the NOx reduction reaction in the HC-SCR catalyst 5, can not effectively reduce the emission of NOx, avoid a situation that To do.

このため、第2の実施の形態では、図3に示したように、ミキサー400、HC−SCR触媒50の排気上流側に、前記酸化触媒40を配設すると共に、該酸化触媒40と前記ミキサー400との間に前記燃料添加ノズル70を配設し、前記酸化触媒40での酸化作用を受けてNOが多く存在する排気に対して燃料(HC)を添加供給することで、前記HC−SCR触媒50のNOx還元作用を効率良く行わせ、以ってNOxの排出量を効果的に低減している。 For this reason, in the second embodiment, as shown in FIG. 3, the oxidation catalyst 40 is disposed upstream of the mixer 400 and the HC-SCR catalyst 50, and the oxidation catalyst 40 and the mixer are arranged. The fuel addition nozzle 70 is disposed between the exhaust catalyst 400 and the fuel (HC) is added to the exhaust gas in which a large amount of NO 2 exists due to the oxidation action of the oxidation catalyst 40, whereby the HC− The NOx reduction action of the SCR catalyst 50 is efficiently performed, so that the NOx emission amount is effectively reduced.

なお、前記HC−SCR触媒50の排気上流側に設けられるミキサー400は、本発明に係る混合手段に相当し、例えば、排気と燃料添加ノズル71から添加供給された燃料(HC)とを良好にミキシングするための装置で、例えば、図4に示すように、複数の開口部420を有する複数の板状部材410を、隣接する板状部材410の開口部420が排気の流れ方向において同一位置にならないように配設されて構成されている。これにより、排気と燃料添加ノズル71から添加供給された燃料(HC)とが良好にミキシングされた状態で、排気下流側のHC−SCR触媒50へ流入することになる。   The mixer 400 provided on the exhaust upstream side of the HC-SCR catalyst 50 corresponds to the mixing means according to the present invention. For example, the exhaust and the fuel (HC) added and supplied from the fuel addition nozzle 71 are excellent. For example, as shown in FIG. 4, a plurality of plate-like members 410 having a plurality of openings 420 are arranged at the same position in the exhaust flow direction. It is arranged so that it does not become. As a result, the exhaust gas and the fuel (HC) supplied and supplied from the fuel addition nozzle 71 are mixed well and flow into the HC-SCR catalyst 50 on the exhaust downstream side.

なお、ミキサー400は、図4に例示した構成に限定されるものではなく、排気と燃料添加ノズル71から添加供給された燃料(HC)とをミキシングできるものであれば、本発明に係る混合手段に含まれる。   The mixer 400 is not limited to the configuration illustrated in FIG. 4, and may be any mixing means according to the present invention as long as it can mix the exhaust gas and the fuel (HC) added and supplied from the fuel addition nozzle 71. include.

従って、第2の実施の形態によれば、排気と燃料(HC)とを良好にミキシングすることができるため、第1の実施の形態と比較して、前記HC−SCR触媒50に対して万遍なくHCを供給することができ、以って前記HC−SCR触媒50のNOx還元作用をより一層効率良く行わせることができ、NOxの排出量の低減を一層促進することができる。   Therefore, according to the second embodiment, the exhaust gas and the fuel (HC) can be mixed well. Therefore, compared with the first embodiment, the HC-SCR catalyst 50 is more effective than the first embodiment. HC can be supplied evenly, so that the NOx reduction action of the HC-SCR catalyst 50 can be performed more efficiently, and the reduction of NOx emission can be further promoted.

そして、第2の実施の形態においても、第1の実施の形態と同様、前記HC−SCR触媒50の排気下流側において、PMを触媒化ディーゼルパティキュレートフィルタ60で捕集して排気中からPMを除去することで、排気中の各種の有害物質の大気中への排出を抑制することができる。   In the second embodiment, as in the first embodiment, PM is collected by the catalyzed diesel particulate filter 60 on the exhaust downstream side of the HC-SCR catalyst 50, and PM is extracted from the exhaust gas. By removing, various harmful substances in the exhaust can be suppressed from being released into the atmosphere.

上記各実施の形態において、HC−SCR触媒50は、特にその種類・形状・構造等は限定されるものではないが、例えば、活性金属が白金(例えば、0.01〜5.0g/l)で、担体がゼオライト或いはアルミナのものを採用することができる。   In each of the above embodiments, the type, shape, structure, etc. of the HC-SCR catalyst 50 are not particularly limited. For example, the active metal is platinum (for example, 0.01 to 5.0 g / l). In this case, it is possible to employ a carrier having zeolite or alumina.

また、上記各実施の形態において、酸化触媒40は、特にその種類・形状・構造等は限定されるものではないが、例えば、活性金属が白金(例えば、0.01〜5.0g/l)で、担体がアルミナ系のものを採用することができる。   In each of the above embodiments, the type, shape, structure, etc. of the oxidation catalyst 40 are not particularly limited. For example, the active metal is platinum (for example, 0.01 to 5.0 g / l). Thus, an alumina carrier can be used.

更に、上記各実施の形態において、触媒化ディーゼルパティキュレートフィルタ60は、特にその種類・形状・構造等は限定されるものではないが、例えば、活性金属が白金(例えば、0.01〜5.0g/l)で、担体がアルミナ系のものを採用することができる。   Further, in each of the above embodiments, the type, shape, structure, etc. of the catalyzed diesel particulate filter 60 are not particularly limited. For example, the active metal is platinum (for example, 0.01-5. 0 g / l) and an alumina carrier can be employed.

なお、上述した各実施の形態においては用いられるディーゼルパティキュレートフィルタは、触媒化ディーゼルパティキュレートフィルタ6に限定されるものではなく、通常のディーゼルパティキュレートフィルタや、電気ヒータ付きのディーゼルパティキュレートフィルタなどを採用することができるものである。   In addition, the diesel particulate filter used in each embodiment described above is not limited to the catalyzed diesel particulate filter 6, but a normal diesel particulate filter, a diesel particulate filter with an electric heater, or the like. Can be adopted.

また、ディーゼルパティキュレートフィルタが不要な場合や、ディーゼルパティキュレートフィルタを排気処理装置より更に排気下流側に別個に配設する場合には、図5において他の態様として示すように、排気処理装置から触媒化ディーゼルパティキュレートフィルタ60を省略して構成することもできる。   Further, when the diesel particulate filter is unnecessary, or when the diesel particulate filter is separately disposed on the exhaust downstream side of the exhaust treatment device, as shown as another embodiment in FIG. The catalyzed diesel particulate filter 60 may be omitted.

その他、本発明の要旨を逸脱しない範囲内において、種々変更を加え得ることは勿論である。   Of course, various modifications can be made without departing from the scope of the present invention.

本発明の第1の実施の形態に係る排気処理装置の構成例を示す図である。It is a figure which shows the structural example of the exhaust-gas treatment apparatus which concerns on the 1st Embodiment of this invention. 同上実施の形態によるNOx低減効果を従来と比較して示す図である。It is a figure which shows the NOx reduction effect by embodiment same as the above compared with the past. 本発明の第2の実施の形態に係る排気処理装置の構成例を示す図である。It is a figure which shows the structural example of the exhaust-gas treatment apparatus which concerns on the 2nd Embodiment of this invention. 同上実施例に係るミキサーの構成例を示す図である。It is a figure which shows the structural example of the mixer which concerns on an Example same as the above. 本発明に係る排気処理装置の他の態様の構成例を示す図である。It is a figure which shows the structural example of the other aspect of the exhaust-air-treatment device which concerns on this invention. 従来の排気処理装置の構成例を示す図である。It is a figure which shows the structural example of the conventional exhaust processing apparatus.

符号の説明Explanation of symbols

10 内燃機関
20 排気通路
30、300 排気処理装置
40 酸化触媒
50 HC選択還元型NOx触媒(HC−SCR触媒)
60 触媒化ディーゼルパティキュレートフィルタ
70 燃料添加装置
71 燃料添加ノズル
400 ミキサー
DESCRIPTION OF SYMBOLS 10 Internal combustion engine 20 Exhaust passage 30, 300 Exhaust treatment apparatus 40 Oxidation catalyst 50 HC selective reduction type NOx catalyst (HC-SCR catalyst)
60 Catalyzed diesel particulate filter 70 Fuel addition device 71 Fuel addition nozzle 400 Mixer

Claims (3)

燃焼装置から排気通路を介して排出される排気を処理する排気処理装置であって、
排気中の所定の成分に対して酸化処理を施すための酸化触媒と、
排気通路に炭化水素を供給する炭化水素供給手段と、
NOxを炭化水素と反応させ得るよう反応選択性を高めた炭化水素選択還元型NOx触媒と、
が、排気下流側に向けて、この順番で前記排気通路に介装されることを特徴とする排気処理装置。
An exhaust treatment device for treating exhaust gas discharged from a combustion device through an exhaust passage,
An oxidation catalyst for subjecting predetermined components in the exhaust to oxidation treatment;
Hydrocarbon supply means for supplying hydrocarbons to the exhaust passage;
A hydrocarbon selective reduction type NOx catalyst having enhanced reaction selectivity so that NOx can be reacted with a hydrocarbon;
Are disposed in the exhaust passage in this order toward the exhaust downstream side.
前記炭化水素供給手段と、前記HC選択還元型NOx触媒と、の間に、前記炭化水素供給手段から供給された炭化水素と、前記排気通路を流れる排気と、を混合するための混合手段が介装されることを特徴とする請求項1に記載の排気処理装置。   A mixing means for mixing the hydrocarbon supplied from the hydrocarbon supply means and the exhaust gas flowing through the exhaust passage is interposed between the hydrocarbon supply means and the HC selective reduction type NOx catalyst. The exhaust treatment device according to claim 1, wherein the exhaust treatment device is mounted. 前記排気通路内のパティキュレートマターを捕集するディーゼルパティキュレートフィルタが、前記炭化水素選択還元型NOx触媒の排気下流側において、前記排気通路に介装されることを特徴とする請求項1又は請求項2に記載の排気処理装置。   2. The diesel particulate filter that collects particulate matter in the exhaust passage is interposed in the exhaust passage on the exhaust downstream side of the hydrocarbon selective reduction type NOx catalyst. Item 3. The exhaust treatment apparatus according to Item 2.
JP2006258145A 2006-09-23 2006-09-23 Exhaust treatment device Pending JP2008075610A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2006258145A JP2008075610A (en) 2006-09-23 2006-09-23 Exhaust treatment device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2006258145A JP2008075610A (en) 2006-09-23 2006-09-23 Exhaust treatment device

Publications (1)

Publication Number Publication Date
JP2008075610A true JP2008075610A (en) 2008-04-03

Family

ID=39347930

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2006258145A Pending JP2008075610A (en) 2006-09-23 2006-09-23 Exhaust treatment device

Country Status (1)

Country Link
JP (1) JP2008075610A (en)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2009299677A (en) * 2008-05-15 2009-12-24 Kubota Corp Exhaust device for diesel engine
CN101979847A (en) * 2009-06-17 2011-02-23 通用汽车环球科技运作公司 Exhaust gas treatment system including an HC-SCR and two-way catalyst and method of using the same
US20110047977A1 (en) * 2009-08-21 2011-03-03 Hyundai Motor Company Exhaust device for diesel vehicle
US8158067B2 (en) 2009-09-02 2012-04-17 Hyundai Motor Company NOx reduction device for diesel vehicles
JP2012087703A (en) * 2010-10-20 2012-05-10 Hino Motors Ltd Exhaust treatment device for internal combustion engine
WO2012081464A1 (en) 2010-12-16 2012-06-21 いすゞ自動車株式会社 DEVICE FOR DIAGNOSING CAUSES OF DECREASES IN NOx CONVERSION EFFICIENCY
JP2016109097A (en) * 2014-12-10 2016-06-20 日野自動車株式会社 Exhaust purification device

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH05195756A (en) * 1992-01-21 1993-08-03 Hino Motors Ltd Exhaust gas purification device of engine
JP2000199423A (en) * 1999-01-05 2000-07-18 Mitsubishi Motors Corp Exhaust gas purification system for diesel engine
JP2002235528A (en) * 2001-02-06 2002-08-23 Hino Motors Ltd Exhaust gas purification device
JP2002285834A (en) * 2001-03-28 2002-10-03 Kawasaki Heavy Ind Ltd Method for removing nitrogen oxides from diesel engine exhaust gas
JP2002295244A (en) * 2001-03-28 2002-10-09 Hino Motors Ltd Exhaust gas purification equipment
JP2003232218A (en) * 2002-02-08 2003-08-22 Hino Motors Ltd Engine exhaust gas purification device
JP2004245096A (en) * 2003-02-12 2004-09-02 Ngk Insulators Ltd Plasma reactor

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH05195756A (en) * 1992-01-21 1993-08-03 Hino Motors Ltd Exhaust gas purification device of engine
JP2000199423A (en) * 1999-01-05 2000-07-18 Mitsubishi Motors Corp Exhaust gas purification system for diesel engine
JP2002235528A (en) * 2001-02-06 2002-08-23 Hino Motors Ltd Exhaust gas purification device
JP2002285834A (en) * 2001-03-28 2002-10-03 Kawasaki Heavy Ind Ltd Method for removing nitrogen oxides from diesel engine exhaust gas
JP2002295244A (en) * 2001-03-28 2002-10-09 Hino Motors Ltd Exhaust gas purification equipment
JP2003232218A (en) * 2002-02-08 2003-08-22 Hino Motors Ltd Engine exhaust gas purification device
JP2004245096A (en) * 2003-02-12 2004-09-02 Ngk Insulators Ltd Plasma reactor

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2009299677A (en) * 2008-05-15 2009-12-24 Kubota Corp Exhaust device for diesel engine
US8336302B2 (en) 2008-05-15 2012-12-25 Kubota Corporation Exhaust device for a diesel engine
KR101560835B1 (en) 2008-05-15 2015-10-15 가부시끼 가이샤 구보다 An exhaust device for a diesel engine
CN101979847A (en) * 2009-06-17 2011-02-23 通用汽车环球科技运作公司 Exhaust gas treatment system including an HC-SCR and two-way catalyst and method of using the same
US20110047977A1 (en) * 2009-08-21 2011-03-03 Hyundai Motor Company Exhaust device for diesel vehicle
US8601797B2 (en) * 2009-08-21 2013-12-10 Hyundai Motor Company Exhaust device for diesel vehicle
US8158067B2 (en) 2009-09-02 2012-04-17 Hyundai Motor Company NOx reduction device for diesel vehicles
JP2012087703A (en) * 2010-10-20 2012-05-10 Hino Motors Ltd Exhaust treatment device for internal combustion engine
WO2012081464A1 (en) 2010-12-16 2012-06-21 いすゞ自動車株式会社 DEVICE FOR DIAGNOSING CAUSES OF DECREASES IN NOx CONVERSION EFFICIENCY
US8973431B2 (en) 2010-12-16 2015-03-10 Isuzu Motors Limited Apparatus for diagnosing causes of NOx conversion efficiency degradation
JP2016109097A (en) * 2014-12-10 2016-06-20 日野自動車株式会社 Exhaust purification device

Similar Documents

Publication Publication Date Title
CN101733166B (en) Diesel oxidation catalyst and exhaust system provided with the same
RU2517714C2 (en) Method of removing impurities from diesel engine exhaust gas
US9061245B2 (en) Method for reducing nitrogen oxides in diesel-engine exhaust gases and exhaust gas aftertreatment system for carrying out the method
EP2230001A1 (en) Exhaust gas treatment
US8992869B2 (en) Ammonia oxidation catalyst system
KR20130103502A (en) Combined slip catalyst and hydrocarbon exotherm catalyst
WO2011090189A1 (en) Exhaust purification device and exhaust purification method for diesel engine
CN101550859A (en) Apparatus for purifying exhaust gas
JP2009114930A (en) Exhaust purification device
KR100999616B1 (en) Nitrogen oxide reduction device in exhaust gas
JP2008274851A (en) Exhaust purification device
WO2016001034A1 (en) An exhaust aftertreatment system for a diesel engine
JP5804544B2 (en) Exhaust treatment device for internal combustion engine
JP2011052679A (en) Exhaust gas aftertreatment device for diesel engine
JP2020045860A (en) Exhaust gas purification device
JP2010180861A (en) Exhaust emission control device
JPH05195756A (en) Exhaust gas purification device of engine
JP2008075610A (en) Exhaust treatment device
JP2009150279A (en) Exhaust treatment device
JP2011099333A (en) Exhaust emission control device
JP2004138022A (en) Method of and device for treating diesel exhaust gas
JP2008286059A (en) Exhaust treatment device
JP4272083B2 (en) Exhaust purification equipment
JP2016114011A (en) Exhaust emission control device
JP2007009718A (en) Exhaust purification device

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20090828

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20100225

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20101209

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20110118

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20110317

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20111124

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20120120

A02 Decision of refusal

Free format text: JAPANESE INTERMEDIATE CODE: A02

Effective date: 20120801