JP2006029147A - Exhaust gas cleaning system and exhaust gas cleaning method - Google Patents

Exhaust gas cleaning system and exhaust gas cleaning method Download PDF

Info

Publication number
JP2006029147A
JP2006029147A JP2004206425A JP2004206425A JP2006029147A JP 2006029147 A JP2006029147 A JP 2006029147A JP 2004206425 A JP2004206425 A JP 2004206425A JP 2004206425 A JP2004206425 A JP 2004206425A JP 2006029147 A JP2006029147 A JP 2006029147A
Authority
JP
Japan
Prior art keywords
exhaust gas
reducing agent
urea
cylinder
temperature
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
JP2004206425A
Other languages
Japanese (ja)
Inventor
Masashi Gabe
我部  正志
Taiji Nagaoka
大治 長岡
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.)
Isuzu Motors Ltd
Original Assignee
Isuzu 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 Isuzu Motors Ltd filed Critical Isuzu Motors Ltd
Priority to JP2004206425A priority Critical patent/JP2006029147A/en
Priority to PCT/JP2005/012363 priority patent/WO2006006441A1/en
Publication of JP2006029147A publication Critical patent/JP2006029147A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01NGAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/08Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
    • F01N3/10Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
    • F01N3/18Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control
    • F01N3/20Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control specially adapted for catalytic conversion ; Methods of operation or control of catalytic converters
    • F01N3/2066Selective catalytic reduction [SCR]
    • F01N3/208Control of selective catalytic reduction [SCR], e.g. dosing of reducing agent
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D53/00Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34Chemical or biological purification of waste gases
    • B01D53/74General processes for purification of waste gases; Apparatus or devices specially adapted therefor
    • B01D53/86Catalytic processes
    • B01D53/90Injecting reactants
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D53/00Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34Chemical or biological purification of waste gases
    • B01D53/92Chemical or biological purification of waste gases of engine exhaust gases
    • B01D53/94Chemical or biological purification of waste gases of engine exhaust gases by catalytic processes
    • B01D53/9445Simultaneously removing carbon monoxide, hydrocarbons or nitrogen oxides making use of three-way catalysts [TWC] or four-way-catalysts [FWC]
    • B01D53/9454Simultaneously removing carbon monoxide, hydrocarbons or nitrogen oxides making use of three-way catalysts [TWC] or four-way-catalysts [FWC] characterised by a specific device
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01NGAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2610/00Adding substances to exhaust gases
    • F01N2610/02Adding substances to exhaust gases the substance being ammonia or urea
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02BINTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B2275/00Other engines, components or details, not provided for in other groups of this subclass
    • F02B2275/14Direct injection into combustion chamber
    • 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

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Environmental & Geological Engineering (AREA)
  • Health & Medical Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Analytical Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Biomedical Technology (AREA)
  • Combustion & Propulsion (AREA)
  • Toxicology (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Exhaust Gas After Treatment (AREA)
  • Exhaust Gas Treatment By Means Of Catalyst (AREA)
  • Output Control And Ontrol Of Special Type Engine (AREA)

Abstract

<P>PROBLEM TO BE SOLVED: To provide an exhaust gas cleaning system and an exhaust gas cleaning method capable of improving the low temperature activity of a selective contact reduction catalyst for removal of NOx using urea water solution without using ammonia which is a dangerous solution, and difficult to handle with. <P>SOLUTION: In the exhaust gas cleaning system 10, the selective contact reduction catalyst 16 to remove nitrogen oxygen is provided in an exhaust passage 4 of an internal combustion engine 1 so as to remove nitrogen oxide in the exhaust gas. A feeder 14 of a reducing agent into an exhaust pipe is provided in the exhaust passage on the upstream side of the selective contact reduction catalyst 16. An injector 15 of reducing agent into a cylinder to feed reducing agent into the cylinder 2 of the internal combustion engine 1 is installed. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

本発明は、内燃機関の排気ガス中のNOxを選択接触還元触媒を用いて浄化する排気ガス浄化システム及び排気ガス浄化方法に関するものである。   The present invention relates to an exhaust gas purification system and an exhaust gas purification method for purifying NOx in exhaust gas of an internal combustion engine using a selective catalytic reduction catalyst.

ディーゼルエンジン等のエンジン(内燃機関)から排出される微粒子状物質(PM)、NOx、COそしてHC等は、年々規制が強化されてきている。この規制の強化に伴い、エンジンの改良のみでは規制値への対応ができなくなってきている。そこで、エンジンに触媒を用いた排気ガス後処理装置を着装して、エンジンから排出されるこれらの物質を低減する技術が採用されている。   Regulations for particulate matter (PM), NOx, CO, HC, and the like discharged from an engine (internal combustion engine) such as a diesel engine have been strengthened year by year. Along with this stricter regulation, it has become impossible to meet the regulation value only by improving the engine. Therefore, a technique is adopted in which an exhaust gas aftertreatment device using a catalyst is attached to the engine to reduce these substances discharged from the engine.

この従来技術の一つに、図4に示すような、選択接触還元触媒(SCR触媒)に尿素を供給して、排気ガス中のNOxを浄化する排気ガス浄化システム20がある。このシステム20は、34%程度の尿素水溶液を貯蔵する尿素タンク21と尿素水排気管内噴射弁22を有する尿素噴射システムと、尿素加水分解機能及びアンモニア還元機能を有する選択接触還元触媒23とを有して構成される。   As one of the prior arts, there is an exhaust gas purification system 20 for purifying NOx in exhaust gas by supplying urea to a selective catalytic reduction catalyst (SCR catalyst) as shown in FIG. This system 20 includes a urea injection system having a urea tank 21 for storing about 34% urea aqueous solution and a urea water exhaust pipe injection valve 22, and a selective catalytic reduction catalyst 23 having a urea hydrolysis function and an ammonia reduction function. Configured.

この排気ガス浄化システム20では、尿素タンク21から尿素水排気管内噴射弁22により排気通路(排気管)4内に添加された尿素は、前段の加水分解機能によって、「(NH2 2 CO+H2 O→2NH3 +CO2 」の反応により、排気ガス中の熱と燃焼によって生成された水蒸気からアンモニアを生成する。 In this exhaust gas purification system 20, urea added from the urea tank 21 into the exhaust passage (exhaust pipe) 4 by the urea water exhaust pipe injection valve 22 is converted into “(NH 2 ) 2 CO + H 2 by the hydrolysis function of the previous stage. By the reaction of “O → 2NH 3 + CO 2 ”, ammonia is generated from the heat in the exhaust gas and the water vapor generated by the combustion.

そして、後段のアンモニア還元機能により、この生成したアンモニアを還元剤として、「6NO+4NH3 →5N2 +6H2 O」と「4NO+4NH3 +O2 →4N2 +6H2 O」の反応により、選択接触NOx還元を行いNOxを浄化する。この反応は、酸素が共存する場合でも進み、一酸化窒素(NO)の1モルに対して、アンモニア(NH3 )の1モルの反応となる。 Then, by the subsequent ammonia reduction function, selective catalytic NOx reduction is performed by the reaction of “6NO + 4NH 3 → 5N 2 + 6H 2 O” and “4NO + 4NH 3 + O 2 → 4N 2 + 6H 2 O” using the generated ammonia as a reducing agent. To purify NOx. This reaction proceeds even when oxygen coexists, and becomes 1 mol of ammonia (NH 3 ) per 1 mol of nitric oxide (NO).

なお、この選択接触還元触媒23は、尿素加水分解機能を有する触媒を前段に配置し、アンモニア還元機能を有する触媒を後段に配置して形成する場合もあるが、アンモニア還元選択NOx触媒中に加水分解機能を持たせて形成する場合もある。   The selective catalytic reduction catalyst 23 may be formed by arranging a catalyst having a urea hydrolysis function in the previous stage and a catalyst having an ammonia reduction function in the subsequent stage. It may be formed with a decomposition function.

しかしながら、この従来の尿素選択接触還元触媒23を用いた排気ガス浄化システム20では、NOx浄化率が、図3の実線Aで示すように、300℃位から著しく低下してしまうという問題がある。つまり、添加した尿素から前段の加水分解反応によって還元剤のアンモニアを生成しているが、この尿素加水分解反応が吸熱反応であるため、低温における活性が低く、そのために、システム全体として、低温域におけるNOx浄化活性が低下してしまうのである。   However, in the exhaust gas purification system 20 using the conventional urea selective catalytic reduction catalyst 23, there is a problem that the NOx purification rate is remarkably reduced from about 300 ° C. as shown by the solid line A in FIG. In other words, ammonia as a reducing agent is generated from the added urea by the preceding hydrolysis reaction, but since this urea hydrolysis reaction is an endothermic reaction, the activity at low temperatures is low, and as a result, the entire system is in a low temperature range. The NOx purification activity in this will decrease.

一方、図3の破線Bで示すように、直接アンモニアを添加する場合には、選択接触還元触媒において、加水分解反応の必要が無くなるため、低温でもNOx浄化活性は高い。従って、選択接触還元触媒にアンモニアを供給すれば高い低温活性を得ることができる。しかしながら、アンモニアは、危険溶液であり、取り扱いが尿素水溶液ほど手軽にはできないという問題がある。   On the other hand, as shown by the broken line B in FIG. 3, in the case of directly adding ammonia, the selective catalytic reduction catalyst eliminates the need for a hydrolysis reaction, so that the NOx purification activity is high even at low temperatures. Therefore, high ammonia activity can be obtained by supplying ammonia to the selective catalytic reduction catalyst. However, ammonia is a dangerous solution and has a problem that it cannot be handled as easily as an aqueous urea solution.

このアンモニアを使用した排気ガス浄化装置としては、アンモニア化合物添加により選択還元が行われるアンモニア化合物選択還元触媒と、排気ガスの空燃比がリーンのときにNOxを吸蔵し、排気ガス中の酸素濃度が低下すると吸蔵したNOxを放出・還元するNOx吸蔵還元型触媒とを排気通路に備えて、高回転・高負荷運転のときにアンモニア化合物選択還元触媒を機能させ、その他のときにはNOx吸蔵還元型触媒を機能させる内燃機関の排気浄化装置が提案されている(例えば、特許文献1参照。)。   The exhaust gas purifying apparatus using ammonia includes an ammonia compound selective reduction catalyst that performs selective reduction by adding an ammonia compound, and stores NOx when the air-fuel ratio of the exhaust gas is lean, and the oxygen concentration in the exhaust gas is reduced. The exhaust passage is equipped with a NOx occlusion reduction type catalyst that releases and reduces the NOx occluded when it is lowered. The ammonia compound selective reduction catalyst functions during high-speed and high-load operation, and the NOx occlusion reduction type catalyst at other times. An exhaust gas purifying device for an internal combustion engine to function is proposed (for example, refer to Patent Document 1).

しかしながら、この内燃機関の排気浄化装置の場合には、NOx吸蔵還元型触媒は高温の排気ガスに曝されると劣化が激しいので、劣化対策が必要になるという問題や、排気通路の切り替えを必要とする場合には、NOxを吸蔵したNOx吸蔵還元型触媒の再生時の制御が複雑となると共にNOxが大気中へ放出されてしまうというスリップの問題も発生する。   However, in the case of this exhaust gas purification device for an internal combustion engine, the NOx occlusion reduction type catalyst is severely deteriorated when exposed to high-temperature exhaust gas. In this case, the control at the time of regeneration of the NOx occlusion reduction type catalyst that occludes NOx becomes complicated, and the problem of slip that NOx is released into the atmosphere also occurs.

また、触媒を使用することなく、酸化窒素を分解させる脱硝装置として、内燃機関におけるシリンダあるいは排気ポートの排気弁の近接部に、アンモニア、または、アンモニア前駆物質(尿素等)を燃焼排ガス中に添加する噴射弁を設けて、排ガスをキヤリアガスとして適用することにより、機構の小型化、コスト節減とともに脱硝性能、信頼性を向上した内燃機関の排気脱硝装置が提案されている(例えば、特許文献2参照。)。   In addition, as a denitration device that decomposes nitric oxide without using a catalyst, ammonia or an ammonia precursor (such as urea) is added to combustion exhaust gas in the vicinity of the exhaust valve of a cylinder or exhaust port in an internal combustion engine. There has been proposed an exhaust denitration device for an internal combustion engine that is provided with an injection valve that applies exhaust gas as a carrier gas and has improved denitration performance and reliability as well as miniaturization of the mechanism and cost reduction (see, for example, Patent Document 2) .)

しかしながら、この装置では、触媒作用を利用することなく、直接アンモニアで窒素酸化物を還元しているので、触媒利用よりも浄化率が低くなるという問題や、排気ガスが高温の時には、反応が進行してアンモニアが窒素酸化物になってしまうという問題がある。   However, in this device, nitrogen oxides are directly reduced with ammonia without using a catalytic action, so that the purification rate is lower than when using a catalyst, and the reaction proceeds when the exhaust gas is hot. Then, there is a problem that ammonia becomes nitrogen oxides.

また、吸気通路、燃焼室、及び排気通路の少なくとも一つにHC等の還元剤を添加する添加装置を備えて、運転情報と添加量との関係を学習しながら、添加量を最適化しつつ、排気通路の選択還元触媒で浄化する排気浄化装置が提案されている(例えば、特許文献3参照。)。   In addition, an addition device that adds a reducing agent such as HC to at least one of the intake passage, the combustion chamber, and the exhaust passage, while learning the relationship between the operation information and the addition amount, while optimizing the addition amount, An exhaust gas purification device that purifies with a selective reduction catalyst in an exhaust passage has been proposed (see, for example, Patent Document 3).

しかしながら、この装置では、排気系に添加したHCがスモークを発生する場合が有り、HCの燃焼により触媒が高温になるという問題がある。
特許第3518398公報 特許第2592119号公報 特開平10−311212号公報
However, in this apparatus, HC added to the exhaust system may generate smoke, and there is a problem that the catalyst becomes high temperature due to combustion of HC.
Japanese Patent No. 3518398 Japanese Patent No. 2592119 JP-A-10-311212

本発明はこの問題を解決するためになされたものであり、本発明の目的は、危険溶液で取り扱いの難しいアンモニアを使用せずに、尿素水溶液を用いながら、NOx浄化に対する選択接触還元触媒の低温活性を向上できる排気ガス浄化システム及び排気ガス浄化方法を提供することにある。   The present invention has been made to solve this problem, and an object of the present invention is to use a low temperature of a selective catalytic reduction catalyst for NOx purification while using an aqueous urea solution without using ammonia that is difficult to handle in a hazardous solution. An object of the present invention is to provide an exhaust gas purification system and an exhaust gas purification method capable of improving the activity.

上記の目的を達成するための本発明に係る排気ガス浄化システムは、内燃機関の排気通路に窒素酸化物を浄化する選択接触還元触媒を備えて、排気ガス中の窒素酸化物を浄化する排気ガス浄化システムにおいて、前記選択接触還元触媒の上流側に排気通路に還元剤を供給する還元剤排気管内供給装置を備えると共に、内燃機関の筒内に還元剤を供給する還元剤筒内噴射装置を設けて構成される。   In order to achieve the above object, an exhaust gas purification system according to the present invention includes a selective catalytic reduction catalyst that purifies nitrogen oxides in an exhaust passage of an internal combustion engine, and exhaust gas that purifies nitrogen oxides in the exhaust gas. In the purification system, a reducing agent exhaust pipe supply device for supplying the reducing agent to the exhaust passage is provided upstream of the selective catalytic reduction catalyst, and a reducing agent in-cylinder injection device for supplying the reducing agent into the cylinder of the internal combustion engine is provided. Configured.

この還元剤筒内噴射装置には、直接、内燃機関の筒内(シリンダ内)に還元剤を供給する装置のみならず、吸気通路に還元剤を噴射して筒内に還元剤を供給する装置も含む。   This reducing agent in-cylinder injection device not only directly supplies the reducing agent into the cylinder (inside the cylinder) of the internal combustion engine, but also supplies the reducing agent into the cylinder by injecting the reducing agent into the intake passage. Including.

この構成により、排気管尿素噴射に加えて、エンジンの筒内への筒内尿素噴射を併用することができるようになるので、筒内の燃焼熱を利用して尿素を加水分解して、アンモニアを生成することができる。従って、比較的取り扱いが容易な尿素を用いながら、アンモニア添加の場合の選択接触還元触媒効果も奏することができるようになる。従って、尿素添加の場合の選択接触還元触媒効果の低温における活性低下を補うことができ、選択接触還元触媒を使用した排気ガス浄化システムの低温活性を向上できる。   With this configuration, in addition to exhaust pipe urea injection, in-cylinder urea injection into the cylinder of the engine can be used in combination, so urea is hydrolyzed using the combustion heat in the cylinder, and ammonia Can be generated. Therefore, the selective catalytic reduction catalytic effect in the case of ammonia addition can be achieved while using urea that is relatively easy to handle. Therefore, it is possible to compensate for the decrease in activity at a low temperature of the selective catalytic reduction catalyst effect in the case of urea addition, and it is possible to improve the low temperature activity of the exhaust gas purification system using the selective catalytic reduction catalyst.

そして、上記の排気ガス浄化システムにおいて、排気ガス温度が、所定の判定温度を超える場合には、前記還元剤排気管内供給装置により還元剤を排気通路に供給し、排気ガス温度が、前記所定の判定温度以下である場合には、前記還元剤筒内噴射装置により還元剤を筒内に供給するように構成される。   In the exhaust gas purification system, when the exhaust gas temperature exceeds a predetermined determination temperature, the reducing agent exhaust pipe supply device supplies the reducing agent to the exhaust passage, and the exhaust gas temperature is When the temperature is equal to or lower than the determination temperature, the reducing agent is supplied into the cylinder by the reducing agent in-cylinder injection device.

この排気ガス温度に対する所定の判定温度には、排気ガス温度がこの所定の判定温度を超えている場合には、選択接触還元触媒が活性温度を超え、排気ガス温度がこの所定の判定温度以下の場合には、選択接触還元触媒が活性温度以下となる温度が選ばれる。   When the exhaust gas temperature exceeds the predetermined determination temperature, the selective catalytic reduction catalyst exceeds the activation temperature and the exhaust gas temperature is equal to or lower than the predetermined determination temperature for the exhaust gas temperature. In such a case, the temperature at which the selective catalytic reduction catalyst is below the activation temperature is selected.

また、上記の排気ガス浄化システムにおいては、還元剤としては、アンモニア前駆物質である尿素水溶液やカルバミン酸アンモニウム等を用いることもできるが、還元剤が尿素水溶液である場合には取り扱いが容易となるので、尿素水溶液を用いることが好ましい。   In the exhaust gas purification system described above, the reducing agent may be urea aqueous solution or ammonium carbamate that is an ammonia precursor. However, when the reducing agent is urea aqueous solution, the handling becomes easy. Therefore, it is preferable to use an aqueous urea solution.

また、上記の目的を達成するための本発明に係る排気ガス浄化方法は、内燃機関の排気通路に窒素酸化物を浄化する選択接触還元触媒を備えると共に、該選択接触還元触媒の上流側に配置され、排気通路に尿素水溶液を供給する還元剤排気管内供給装置と、内燃機関の筒内に尿素水溶液を供給する還元剤筒内噴射装置を備えて、排気ガス中の窒素酸化物を浄化する排気ガス浄化システムにおいて、前記選択接触還元触媒の温度が尿素の加水分解の活性温度を超える場合には、前記還元剤排気管内供給装置により尿素水溶液を排気通路に供給し、前記選択接触還元触媒の温度が尿素の加水分解の活性温度以下である場合には、前記還元剤筒内噴射装置により尿素水溶液を筒内に供給し、前記還元剤筒内噴射装置より供給された尿素水溶液を、内燃機関の筒内の燃焼熱により、アンモニアに加水分解し、該アンモニアにより、前記選択接触還元触媒で窒素酸化物を浄化する方法として構成される。   In addition, an exhaust gas purification method according to the present invention for achieving the above object includes a selective catalytic reduction catalyst that purifies nitrogen oxides in an exhaust passage of an internal combustion engine, and is disposed upstream of the selective catalytic reduction catalyst. An exhaust gas for purifying nitrogen oxides in exhaust gas, comprising a reducing agent exhaust pipe supply device for supplying urea aqueous solution to the exhaust passage and a reducing agent in-cylinder injection device for supplying urea aqueous solution into the cylinder of the internal combustion engine In the gas purification system, when the temperature of the selective catalytic reduction catalyst exceeds the activation temperature of urea hydrolysis, an aqueous urea solution is supplied to the exhaust passage by the supply device in the reducing agent exhaust pipe, and the temperature of the selective catalytic reduction catalyst Is below the activation temperature of urea hydrolysis, the urea aqueous solution is supplied into the cylinder by the reducing agent in-cylinder injection device, and the urea aqueous solution supplied from the reducing agent in-cylinder injection device is The heat of combustion of the cylinder of the engine, hydrolyzed into ammonia by the ammonia, and a method for purifying nitrogen oxides in the selective catalytic reduction catalyst.

この方法により、比較的取り扱いが容易な尿素を用いながら、選択接触還元触媒の温度によって、筒内尿素噴射と排気管尿素噴射を使い分けて、低温時には、筒内の燃焼熱を利用してアンモニアを選択接触還元触媒に供給することができるので、低温域におけるNOx浄化の活性低下を補うことができる。   With this method, while using urea, which is relatively easy to handle, the in-cylinder urea injection and the exhaust pipe urea injection are selectively used according to the temperature of the selective catalytic reduction catalyst. Since it can supply to a selective catalytic reduction catalyst, the activity fall of NOx purification | cleaning in a low temperature range can be supplemented.

本発明の排気ガス浄化システム及び排気ガス浄化方法によれば、排気管尿素噴射に加えて、エンジンの筒内への筒内尿素噴射を併用することにより、比較的取り扱いが容易な尿素を用いながら、アンモニア添加の場合の選択接触還元触媒効果も奏することができ、尿素添加の場合の選択接触還元触媒効果の低温における活性低下を補うことができ、選択接触還元触媒を使用した排気ガス浄化システムの低温活性を向上できる。   According to the exhaust gas purification system and the exhaust gas purification method of the present invention, in addition to exhaust pipe urea injection, in-cylinder urea injection into the cylinder of the engine is used in combination, while using urea that is relatively easy to handle. In addition, the selective catalytic reduction catalytic effect in the case of ammonia addition can also be exhibited, and the decrease in activity at a low temperature of the selective catalytic reduction catalytic effect in the case of urea addition can be compensated, and the exhaust gas purification system using the selective catalytic reduction catalyst Low temperature activity can be improved.

次に、図面を参照して本発明に係る排気ガス浄化システム及び排気ガス浄化方法の実施の形態について説明する。   Next, an embodiment of an exhaust gas purification system and an exhaust gas purification method according to the present invention will be described with reference to the drawings.

図1に、この排気ガス浄化システム10の構成を示す。この排気ガス浄化システム10では、エンジン(内燃機関)1の排気通路4に、窒素酸化物(NOx)を浄化する選択接触還元触媒(SCR触媒)16を備える。この選択接触還元触媒16は、貴金属(白金等)や遷移金属(銅、コバルト、バナジウム等)を、ゼオライト、シリカ/アルミナ、アルミナ、シリカ、チタニア等の担体に担持して形成される。   FIG. 1 shows the configuration of the exhaust gas purification system 10. In the exhaust gas purification system 10, a selective contact reduction catalyst (SCR catalyst) 16 that purifies nitrogen oxides (NOx) is provided in the exhaust passage 4 of the engine (internal combustion engine) 1. The selective catalytic reduction catalyst 16 is formed by supporting a noble metal (such as platinum) or a transition metal (such as copper, cobalt, or vanadium) on a support such as zeolite, silica / alumina, alumina, silica, or titania.

また、それと共に、この選択接触還元触媒16の上流側に還元剤排気管内供給装置14と、エンジン1の筒内(シリンダ内)2に還元剤を供給する還元剤筒内噴射装置15を設けて構成される。   At the same time, a reducing agent exhaust pipe supply device 14 and a reducing agent in-cylinder injection device 15 for supplying the reducing agent to the cylinder (cylinder) 2 of the engine 1 are provided upstream of the selective catalytic reduction catalyst 16. Composed.

そして、還元剤としての尿素水溶液を、還元剤排気管内供給装置14と還元剤筒内噴射装置15に供給するために、尿素水タンク11と尿素水ポンプ12と尿素水コモンレール13を設ける。また、排気通路4の選択接触還元触媒16の上流側に排気ガス温度センサ17を設ける。   In order to supply the urea aqueous solution as the reducing agent to the reducing agent exhaust pipe supply device 14 and the reducing agent in-cylinder injection device 15, the urea water tank 11, the urea water pump 12, and the urea water common rail 13 are provided. Further, an exhaust gas temperature sensor 17 is provided upstream of the selective catalytic reduction catalyst 16 in the exhaust passage 4.

更に、燃料噴射弁3の制御等を含むエンジン1の制御と共に、還元剤噴射制御を行う制御装置(エンジンコントロールユニット:ECU)18が設けられており、排気ガス温度センサ17からの入力を基に、還元剤排気管内供給装置14と還元剤筒内噴射装置15を制御して、尿素水の供給を制御する。   Further, a control device (engine control unit: ECU) 18 that performs reductant injection control together with control of the engine 1 including control of the fuel injection valve 3 and the like is provided, based on an input from the exhaust gas temperature sensor 17. Then, the reducing agent exhaust pipe supply device 14 and the reducing agent in-cylinder injection device 15 are controlled to control the supply of urea water.

そして、この構成の排気ガス浄化システム10において、排気ガス浄化方法は、図2に例示するような制御フローに従って行われる。   In the exhaust gas purification system 10 having this configuration, the exhaust gas purification method is performed according to the control flow illustrated in FIG.

エンジン1の運転が開始され、排気ガスの浄化が始まると、図2の制御フローも開始され、ステップS11で排気ガス温度センサ17により排気ガス温度Tgの検出が行われる。そして、次のステップS12で、排気ガス温度Tgが所定の判定温度Tg0と比較される。   When the operation of the engine 1 is started and the purification of the exhaust gas is started, the control flow of FIG. 2 is also started, and the exhaust gas temperature sensor 17 detects the exhaust gas temperature Tg in step S11. Then, in the next step S12, the exhaust gas temperature Tg is compared with a predetermined determination temperature Tg0.

この排気ガス温度Tgに対する所定の判定温度Tg0には、排気ガス温度Tgがこの所定の判定温度Tg0を超えている場合には、選択接触還元触媒16の触媒温度Tcが加水分解のための活性温度Tc0を超え、また、排気ガス温度Tgがこの所定の判定温度Tg0以下の場合には、選択接触還元触媒16の触媒温度Tcが加水分解のための活性温度Tc0以下となる温度が選ばれる。この温度は、例えば、燃焼室出口の排気ガス温度で、350℃程度、選択接触還元触媒16の入口の排気ガス温度Tgや触媒温度Tcで250℃〜300℃である。   When the exhaust gas temperature Tg exceeds the predetermined determination temperature Tg0, the catalyst temperature Tc of the selective catalytic reduction catalyst 16 is the activation temperature for hydrolysis when the exhaust gas temperature Tg exceeds the predetermined determination temperature Tg0 with respect to the exhaust gas temperature Tg. When Tc0 is exceeded and the exhaust gas temperature Tg is equal to or lower than the predetermined determination temperature Tg0, a temperature at which the catalyst temperature Tc of the selective catalytic reduction catalyst 16 is equal to or lower than the activation temperature Tc0 for hydrolysis is selected. This temperature is, for example, about 350 ° C. at the exhaust gas temperature at the outlet of the combustion chamber, and 250 ° C. to 300 ° C. at the exhaust gas temperature Tg and the catalyst temperature Tc at the inlet of the selective catalytic reduction catalyst 16.

このステップS12の比較で、排気ガス温度Tgが所定の判定温度Tg0以下の場合には、ステップS13で、筒内尿素噴射制御を行って、還元剤筒内噴射装置15より筒内2に尿素水溶液を供給すると共に、排気管尿素噴射制御を中止して、還元剤排気管内供給装置14からの排気通路4内への尿素水溶液の供給を停止する。これを所定の時間の間、即ち、排気ガス温度Tgをチェックするインターバルの間行い、ステップS11に戻る。   If the exhaust gas temperature Tg is equal to or lower than the predetermined determination temperature Tg0 in the comparison in step S12, in-cylinder urea injection control is performed in step S13, and the urea aqueous solution is introduced into the cylinder 2 from the reducing agent in-cylinder injection device 15. And the exhaust pipe urea injection control is stopped, and the supply of the aqueous urea solution from the reducing agent exhaust pipe supply device 14 into the exhaust passage 4 is stopped. This is performed for a predetermined time, that is, during an interval for checking the exhaust gas temperature Tg, and the process returns to step S11.

この排気ガス温度Tgが低く、NOx浄化活性が低くなるエンジン1の低負荷運転領域の極微小噴射量では、尿素を主燃焼前の圧縮始め行程でエンジン1の筒内2に噴射し、主燃焼の燃焼熱を利用して尿素加水分解反応を行わせてアンモニアを生成する。噴射量が多くなるに従い燃焼温度が高くなり、アンモニアが窒素酸化物になってしまうので、筒内2の温度が比較的低い温度のときに噴射する。   At a very small injection amount in the low load operation region of the engine 1 where the exhaust gas temperature Tg is low and the NOx purification activity is low, urea is injected into the cylinder 2 of the engine 1 in the compression start stroke before the main combustion, and the main combustion Ammonia is generated by performing a urea hydrolysis reaction using the heat of combustion of the. As the injection amount increases, the combustion temperature increases, and ammonia becomes nitrogen oxides. Therefore, injection is performed when the temperature in the cylinder 2 is relatively low.

より具体的には、低負荷運転領域でもある程度の噴射量がある場合には、メイン噴射終了後から、ATDC90°位までの範囲で尿素噴射を行う。吸熱反応であるので、ある程度の温度が必要であり、また、ADTC90°をすぎると、噴射した尿素水溶液がシリンダ内面に付着し、この尿素水溶液がエンジンオイルの希釈や錆の発生の原因となるためである。また、燃焼温度や排気ガスの温度により噴射時期を決定し、温度が高いとき程、遅い方にずらす。   More specifically, when there is a certain amount of injection even in the low load operation region, urea injection is performed in a range from the end of main injection to about ATDC 90 °. Since it is an endothermic reaction, a certain temperature is required, and if it exceeds ADTC 90 °, the injected urea aqueous solution adheres to the cylinder inner surface, and this urea aqueous solution causes dilution of engine oil and generation of rust. It is. Also, the injection timing is determined based on the combustion temperature and the exhaust gas temperature, and the higher the temperature, the slower it is shifted.

そして、この筒内2で発生したアンモニアが選択接触還元触媒16に供給される。そのため、前段尿素加水分解反応が不要となり、低温でもNOxを還元できるようになる。なお、直接、筒内2に尿素水溶液を噴射する代わりに、吸気行程中に、吸気通路(吸気管)5に尿素を噴射して筒内2に尿素を供給してもよい。   The ammonia generated in the cylinder 2 is supplied to the selective catalytic reduction catalyst 16. Therefore, the pre-stage urea hydrolysis reaction becomes unnecessary, and NOx can be reduced even at a low temperature. Instead of injecting the urea aqueous solution directly into the cylinder 2, urea may be injected into the intake passage (intake pipe) 5 and supplied to the cylinder 2 during the intake stroke.

また、ステップS12の比較で、排気ガス温度Tgが所定の判定温度Tg0を超えている場合には、ステップS14で、排気管尿素噴射制御を行って、還元剤排気管内供給装置14より排気通路4内に尿素水溶液を供給すると共に、筒内尿素噴射制御を中止して、還元剤筒内噴射装置15からの筒内2への尿素水溶液の供給を停止する。これを所定の時間の間、即ち、排気ガス温度Tgをチェックするインターバルの間行い、ステップS11に戻る。   If the exhaust gas temperature Tg exceeds the predetermined judgment temperature Tg0 in the comparison in step S12, exhaust pipe urea injection control is performed in step S14, and the exhaust passage 4 is supplied from the reducing agent exhaust pipe supply device 14. The urea aqueous solution is supplied to the inside, and the in-cylinder urea injection control is stopped, and the supply of the urea aqueous solution from the reducing agent in-cylinder injection device 15 to the in-cylinder 2 is stopped. This is performed for a predetermined time, that is, during an interval for checking the exhaust gas temperature Tg, and the process returns to step S11.

この排気ガス温度Tgが高く、NOx浄化活性が高くなるエンジン1の中・高負荷運転領域では、選択接触還元触媒16で尿素を加水分解できるので、排気通路4に供給された尿素を前段尿素加水分解反応によりアンモニアに変えて、NOxを浄化することができる。また、高温度域において筒内尿素水噴射を中止することにより、筒内において、尿素が高温のために反応が進行してNOxになってしまうのを防止することができる。   In the middle / high load operation region of the engine 1 where the exhaust gas temperature Tg is high and the NOx purification activity is high, urea can be hydrolyzed by the selective catalytic reduction catalyst 16, so that the urea supplied to the exhaust passage 4 can be hydrolyzed in the preceding stage. NOx can be purified by changing to ammonia by a decomposition reaction. In addition, by stopping the in-cylinder urea water injection in the high temperature range, it is possible to prevent the reaction from proceeding to NOx due to the high temperature of urea in the cylinder.

そして、これらの各ステップの繰り返しが、エンジン1の運転が停止されるまで行われる。エンジンキーがオフされると、ステップS20の割り込みが生じ、ステップS21で筒内尿素噴射制御の停止と排気管尿素噴射制御の停止等の終了作業を行ってから、この制御フローをストップする。   These steps are repeated until the operation of the engine 1 is stopped. When the engine key is turned off, an interruption in step S20 occurs, and in step S21, after completion work such as stopping in-cylinder urea injection control and stopping exhaust pipe urea injection control, the control flow is stopped.

この制御により、排気ガス温度Tgが、所定の判定温度Tcを超える場合には、還元剤排気管内供給装置14により還元剤である尿素水溶液を排気通路4に供給し、排気ガス温度Tgが、所定の判定温度Tc以下である場合には、還元剤筒内噴射装置15により尿素水溶液を筒内2に供給することができる。   By this control, when the exhaust gas temperature Tg exceeds a predetermined determination temperature Tc, the reducing agent exhaust pipe supply device 14 supplies the urea aqueous solution, which is a reducing agent, to the exhaust passage 4, and the exhaust gas temperature Tg is predetermined. When the temperature is equal to or lower than the determination temperature Tc, the reducing agent in-cylinder injection device 15 can supply the urea aqueous solution to the cylinder 2.

上記の構成の排気ガス浄化システム及び排気ガス浄化方法によれば、排気通路4内への尿素水噴射に加えて、エンジン1の筒内2への尿素水噴射を併用することができるようになるので、筒内2の燃焼熱を利用して尿素を加水分解して、アンモニアを生成することができる。そのため、比較的取り扱いが容易な尿素を用いながら、アンモニア添加の場合の選択接触還元触媒効果も奏することができるようになる。   According to the exhaust gas purification system and the exhaust gas purification method configured as described above, urea water injection into the cylinder 2 of the engine 1 can be used in addition to urea water injection into the exhaust passage 4. Therefore, urea can be hydrolyzed using the combustion heat in the cylinder 2 to generate ammonia. Therefore, the selective catalytic reduction catalytic effect in the case of ammonia addition can be exhibited while using urea that is relatively easy to handle.

従って、尿素添加の場合の選択接触還元触媒効果の低温における活性低下を補うことができ、選択接触還元触媒16を使用した排気ガス浄化システム10のNOxの浄化に対する低温活性を向上できる。   Therefore, it is possible to compensate for the decrease in activity at a low temperature of the selective catalytic reduction catalyst effect in the case of urea addition, and it is possible to improve the low temperature activity for NOx purification of the exhaust gas purification system 10 using the selective catalytic reduction catalyst 16.

本発明に係る実施の形態の排気ガス浄化システムの構成を示す図である。It is a figure which shows the structure of the exhaust gas purification system of embodiment which concerns on this invention. 本発明に係る実施の形態の排気ガス浄化方法の制御の例を示す図である。It is a figure which shows the example of control of the exhaust gas purification method of embodiment which concerns on this invention. 尿素添加とアンモニア添加の場合の選択接触還元触媒のNOx浄化率と触媒温度との関係を示す図である。It is a figure which shows the relationship between the NOx purification rate of a selective catalytic reduction catalyst in the case of urea addition and ammonia addition, and catalyst temperature. 従来技術の排気ガス浄化システムの構成を示す図である。It is a figure which shows the structure of the exhaust-gas purification system of a prior art.

符号の説明Explanation of symbols

1 エンジン(内燃機関)
2 筒内(シリンダ内)
3 燃焼噴射弁
4 排気通路(排気管)
10 排気ガス浄化システム
11 尿素水タンク
12 尿素水ポンプ
13 尿素水コモンレール
14 還元剤排気管内供給装置
15 還元剤筒内噴射装置
16 選択接触還元触媒(SCR触媒)
17 排気ガス温度センサ
18 制御装置(ECU)
Tg 排気ガス温度
Tg0 所定の判定温度
Tc 触媒温度
Tc0 加水分解のための活性温度
1 engine (internal combustion engine)
2 In-cylinder (inside cylinder)
3 Combustion injection valve 4 Exhaust passage (exhaust pipe)
DESCRIPTION OF SYMBOLS 10 Exhaust gas purification system 11 Urea water tank 12 Urea water pump 13 Urea water common rail 14 Reducing agent exhaust pipe supply device 15 Reducing agent cylinder injection device 16 Selective contact reduction catalyst (SCR catalyst)
17 Exhaust gas temperature sensor 18 Control unit (ECU)
Tg Exhaust gas temperature Tg0 Predetermined judgment temperature Tc Catalyst temperature Tc0 Activation temperature for hydrolysis

Claims (4)

内燃機関の排気通路に窒素酸化物を浄化する選択接触還元触媒を備えて、排気ガス中の窒素酸化物を浄化する排気ガス浄化システムにおいて、前記選択接触還元触媒の上流側に排気通路に還元剤を供給する還元剤排気管内供給装置を備えると共に、内燃機関の筒内に還元剤を供給する還元剤筒内噴射装置を設けたことを特徴とする排気ガス浄化システム。   An exhaust gas purification system that includes a selective catalytic reduction catalyst that purifies nitrogen oxides in an exhaust passage of an internal combustion engine, and purifies nitrogen oxides in exhaust gas. An exhaust gas purification system comprising: a reducing agent exhaust pipe supply device that supplies a reducing agent, and a reducing agent in-cylinder injection device that supplies the reducing agent into a cylinder of the internal combustion engine. 排気ガス温度が、所定の判定温度を超える場合には、前記還元剤排気管内供給装置により還元剤を排気通路に供給し、排気ガス温度が、前記所定の判定温度以下である場合には、前記還元剤筒内噴射装置により還元剤を筒内に供給することを特徴とする請求項1記載の排気ガス浄化システム。   When the exhaust gas temperature exceeds a predetermined determination temperature, the reducing agent exhaust pipe supply device supplies the reducing agent to the exhaust passage, and when the exhaust gas temperature is equal to or lower than the predetermined determination temperature, The exhaust gas purification system according to claim 1, wherein the reducing agent is supplied into the cylinder by the reducing agent in-cylinder injection device. 前記還元剤が、尿素水溶液であることを特徴とする請求項1又は2に記載の排気ガス浄化システム。   The exhaust gas purification system according to claim 1 or 2, wherein the reducing agent is an aqueous urea solution. 内燃機関の排気通路に窒素酸化物を浄化する選択接触還元触媒を備えると共に、該選択接触還元触媒の上流側に配置され、排気通路に尿素水溶液を供給する還元剤排気管内供給装置と、内燃機関の筒内に尿素水溶液を供給する還元剤筒内噴射装置を備えて、排気ガス中の窒素酸化物を浄化する排気ガス浄化システムにおいて、前記選択接触還元触媒の温度が尿素の加水分解の活性温度を超える場合には、前記還元剤排気管内供給装置により尿素水溶液を排気通路に供給し、前記選択接触還元触媒の温度が尿素の加水分解の活性温度以下である場合には、前記還元剤筒内噴射装置により尿素水溶液を筒内に供給し、前記還元剤筒内噴射装置より供給された尿素水溶液を、内燃機関の筒内の燃焼熱により、アンモニアに加水分解し、該アンモニアにより、前記選択接触還元触媒で窒素酸化物を浄化することを特徴とする排気ガス浄化方法。
A reducing agent exhaust pipe supply device that includes a selective catalytic reduction catalyst that purifies nitrogen oxides in an exhaust passage of an internal combustion engine, is disposed upstream of the selective catalytic reduction catalyst, and supplies an aqueous urea solution to the exhaust passage, and an internal combustion engine The exhaust gas purification system for purifying nitrogen oxides in the exhaust gas, comprising a reducing agent in-cylinder injection device for supplying urea aqueous solution into the cylinder of the exhaust gas, wherein the temperature of the selective catalytic reduction catalyst is the activation temperature of urea hydrolysis If the temperature of the selective catalytic reduction catalyst is equal to or lower than the activation temperature of urea hydrolysis, the reducing agent exhaust pipe supply device supplies urea aqueous solution to the exhaust passage. A urea aqueous solution is supplied into the cylinder by the injection device, and the urea aqueous solution supplied from the reducing agent in-cylinder injection device is hydrolyzed into ammonia by the combustion heat in the cylinder of the internal combustion engine, and the ammonia More, the exhaust gas purification method, characterized in that purifies nitrogen oxides in the selective catalytic reduction catalyst.
JP2004206425A 2004-07-13 2004-07-13 Exhaust gas cleaning system and exhaust gas cleaning method Pending JP2006029147A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
JP2004206425A JP2006029147A (en) 2004-07-13 2004-07-13 Exhaust gas cleaning system and exhaust gas cleaning method
PCT/JP2005/012363 WO2006006441A1 (en) 2004-07-13 2005-07-05 System and method for purification of exhaust gas

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2004206425A JP2006029147A (en) 2004-07-13 2004-07-13 Exhaust gas cleaning system and exhaust gas cleaning method

Publications (1)

Publication Number Publication Date
JP2006029147A true JP2006029147A (en) 2006-02-02

Family

ID=35783785

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2004206425A Pending JP2006029147A (en) 2004-07-13 2004-07-13 Exhaust gas cleaning system and exhaust gas cleaning method

Country Status (2)

Country Link
JP (1) JP2006029147A (en)
WO (1) WO2006006441A1 (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100876161B1 (en) 2008-03-24 2008-12-31 박정봉 Total nox control process
WO2009063866A1 (en) * 2007-11-13 2009-05-22 Toyota Jidosha Kabushiki Kaisha Exhaust purification system for internal combustion engine
WO2010125659A1 (en) * 2009-04-28 2010-11-04 トヨタ自動車株式会社 Exhaust emission control device for engine
WO2011132604A1 (en) * 2010-04-22 2011-10-27 トヨタ自動車株式会社 Device for controlling internal combustion engine
DE102019203660A1 (en) * 2019-03-19 2020-04-30 Audi Ag Method for operating a drive device, corresponding drive device and use of an aqueous urea solution for operating a drive device
CN112983603A (en) * 2019-12-17 2021-06-18 卡特彼勒公司 Post-processing system and method

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2009081227A1 (en) * 2007-12-20 2009-07-02 Renault Trucks Six-stroke internal combustion engine, method of operation of such an engine and vehicle equipped with such an engine
US20120004830A1 (en) * 2009-03-25 2012-01-05 Toyota Jidosha Kabushiki Kaisha Controller for internal combustion engine

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS55104513A (en) * 1979-02-06 1980-08-11 Nissan Motor Co Ltd Exhaust-gas purifying system for internal combustion engine
JPS6119940A (en) * 1984-07-07 1986-01-28 Mitsubishi Heavy Ind Ltd Method of introducing intake-air and discharging exhaust gas
JPH03213614A (en) * 1990-01-18 1991-09-19 Fuel Tec Japan Kk Exhaust gas disposing device for diesel engine
JPH0674023A (en) * 1992-08-28 1994-03-15 Isuzu Motors Ltd Exhaust gas purifying device of internal combustion engine
JP3391587B2 (en) * 1994-11-18 2003-03-31 株式会社小松製作所 Exhaust denitration equipment for diesel engines

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2009063866A1 (en) * 2007-11-13 2009-05-22 Toyota Jidosha Kabushiki Kaisha Exhaust purification system for internal combustion engine
JP2009138731A (en) * 2007-11-13 2009-06-25 Toyota Motor Corp Exhaust emission control system for internal combustion engine
US8336296B2 (en) 2007-11-13 2012-12-25 Toyota Jidosha Kabushiki Kaisha Exhaust gas purification system for internal combustion engine
KR100876161B1 (en) 2008-03-24 2008-12-31 박정봉 Total nox control process
JP5293811B2 (en) * 2009-04-28 2013-09-18 トヨタ自動車株式会社 Engine exhaust purification system
WO2010125659A1 (en) * 2009-04-28 2010-11-04 トヨタ自動車株式会社 Exhaust emission control device for engine
US8656703B2 (en) 2009-04-28 2014-02-25 Toyota Jidosha Kabushiki Kaisha Exhaust purification device for engine
US20120036842A1 (en) * 2009-04-28 2012-02-16 Toyota Jidosha Kabushiki Kaisha Exhaust purification device for engine
CN102414405A (en) * 2009-04-28 2012-04-11 丰田自动车株式会社 Exhaust emission control device for engine
US8534237B2 (en) 2010-04-22 2013-09-17 Toyota Jidosha Kabushiki Kaisha Control system of internal combustion engine
JP5397541B2 (en) * 2010-04-22 2014-01-22 トヨタ自動車株式会社 Control device for internal combustion engine
WO2011132604A1 (en) * 2010-04-22 2011-10-27 トヨタ自動車株式会社 Device for controlling internal combustion engine
US8720417B1 (en) 2010-04-22 2014-05-13 Toyota Jidosha Kabushiki Kaisha Control system of internal combustion engine
DE102019203660A1 (en) * 2019-03-19 2020-04-30 Audi Ag Method for operating a drive device, corresponding drive device and use of an aqueous urea solution for operating a drive device
CN112983603A (en) * 2019-12-17 2021-06-18 卡特彼勒公司 Post-processing system and method
US11143078B2 (en) 2019-12-17 2021-10-12 Caterpillar Inc. Aftertreatment system and method

Also Published As

Publication number Publication date
WO2006006441A1 (en) 2006-01-19

Similar Documents

Publication Publication Date Title
JP4274270B2 (en) NOx purification system and control method of NOx purification system
JP5087836B2 (en) Exhaust gas purification system control method and exhaust gas purification system
JP4947036B2 (en) Engine exhaust purification method
JP5630024B2 (en) Diesel engine exhaust purification device and exhaust purification method
JP6264261B2 (en) Exhaust gas purification system
JP2013124610A (en) Exhaust emission control device of internal combustion engine
JP2010180861A (en) Exhaust emission control device
KR20090064008A (en) Apparatus for reducing nitrogen oxide cotained in exhaust gas
WO2006006441A1 (en) System and method for purification of exhaust gas
EP2112340B1 (en) Exhaust gas purification device for internal combustion engine
JP2007002697A (en) Exhaust emission control device
JP4007046B2 (en) Exhaust gas purification device for internal combustion engine
JP2007205267A (en) Exhaust emission control device
WO2017191813A1 (en) Exhaust gas purification system for internal combustion engine, and exhaust gas purification method for internal combustion engine
JP5003042B2 (en) Exhaust gas purification system
JP2010185369A (en) Fuel supply device of engine
JP6915424B2 (en) Exhaust gas purification system and regeneration control method
JP2008075620A (en) Exhaust emission control device
JP6809391B2 (en) Injection device
KR100587807B1 (en) Control method of SCR
JP2003286827A (en) Exhaust emission control device for internal combustion engine
JP2019190425A (en) Exhaust emission control device and vehicle
JP5476770B2 (en) Exhaust gas purification system and control method of exhaust gas purification system
WO2016006657A1 (en) Exhaust purification system
WO2016006656A1 (en) Exhaust purification system

Legal Events

Date Code Title Description
A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20051108

A02 Decision of refusal

Free format text: JAPANESE INTERMEDIATE CODE: A02

Effective date: 20060516