公开(公告)号：US06192675B1

公开(公告)日：2001-02-27

申请号：US09184047

申请日：1998-11-02

申请人： Shinya Hirota ,  Toshiaki Tanaka ,  Kouji Yoshizaki ,  Nobumoto Ohashi ,  Eiji Iwasaki ,  Kazuhiro Itoh

发明人： Shinya Hirota ,  Toshiaki Tanaka ,  Kouji Yoshizaki ,  Nobumoto Ohashi ,  Eiji Iwasaki ,  Kazuhiro Itoh

IPC分类号： F01N300

CPC分类号： F01N3/2066 ,  B01D53/9431 ,  B01D53/9495 ,  F01N3/2053 ,  F01N13/0097 ,  F01N2610/02 ,  F01N2610/03 ,  F01N2610/04 ,  F02B37/18 ,  Y02T10/144 ,  Y02T10/24

摘要： In an exhaust gas purification device, a catalytic converter containing selective reduction catalysts is disposed in an exhaust gas passage of an internal combustion engine capable of being operated at a lean air-fuel ratio. The catalytic converter includes a plurality of the selective reduction catalysts disposed in series in the casing of the catalytic converter. Bypass passages which supply the exhaust gas to downstream selective reduction catalysts in the casing by bypassing the upstream catalysts are provided. When a reducing agent is supplied to the exhaust gas upstream of the converter, a part of the supplied reducing agent directly reaches the downstream selective reduction catalyst through the bypass passages without being oxidized by the upstream selective reduction catalysts. Therefore, the NOx purifying abilities of the downstream catalysts are improved and the formation of sulfates on the downstream catalysts is suppressed.

摘要翻译： 在废气净化装置中，含有选择还原催化剂的催化转化器设置在能够以稀薄空燃比运转的内燃机的排气通路中。 催化转化器包括多个选择性还原催化剂串联设置在催化转化器的壳体中。 提供了通过绕过上游催化剂将排气供给到壳体中的下游选择性还原催化剂的旁路通道。 当还原剂被供给到转化器上游的废气时，所供给的还原剂的一部分通过旁路通道直接到达下游选择还原催化剂，而不被上游选择还原催化剂氧化。 因此，下游催化剂​​的NOx净化能力得到改善，并且抑制了下游催化剂​​上形成硫酸盐。

公开(公告)号：US06233927B1

公开(公告)日：2001-05-22

申请号：US09362287

申请日：1999-07-27

申请人： Shinya Hirota ,  Toshiaki Tanaka ,  Nobumoto Ohashi ,  Kazuhiro Itoh ,  Eiji Iwasaki ,  Kouji Yoshizaki

发明人： Shinya Hirota ,  Toshiaki Tanaka ,  Nobumoto Ohashi ,  Kazuhiro Itoh ,  Eiji Iwasaki ,  Kouji Yoshizaki

IPC分类号： F01N300

CPC分类号： F01N3/0842 ,  F01N3/0231 ,  F01N3/027 ,  F01N3/0821 ,  F01N3/0878 ,  F01N3/30 ,  F01N2410/04 ,  Y10S55/30

摘要： According to the present invention, there is provided an exhaust gas purification device, comprising a NOx absorbent arranged in an exhaust passage of an engine for absorbing NOx therein when an air-fuel ratio of an exhaust gas flowing into the NOx absorbent is lean, the NOx absorbent discharging NOx absorbed therein when a concentration of the oxygen in the exhaust gas flowing into the NOx absorbent decreases, a trapping element arranged in the exhaust passage upstream of the NOx absorbent for trapping particulates, a processing element for processing the particulates trapped in the trapping element to regenerate the trapping element, and a preventing element for preventing the exhaust gas from flowing into the NOx absorbent from the trapping element when the trapping element is regenerated.

摘要翻译： 根据本发明，提供了一种废气净化装置，其包括当流入所述NOx吸收剂的排气的空燃比稀的时候，所述排气净化装置包括设置在用于吸收NOx的发动机的排气通道中的NOx吸收体， NOx吸收剂，其中，当流入NOx吸收剂的排气中的氧浓度降低时，吸收NOx的吸收剂中的NOx吸收剂，用于捕集微粒的NOx吸收剂上游排出通道的捕集元件， 捕获元件以再生捕集元件，以及防止元件，用于在捕获元件再生时防止废气从捕集元件中流入NOx吸收剂。

公开(公告)号：US6058700A

公开(公告)日：2000-05-09

申请号：US83738

申请日：1998-05-22

申请人： Tetsuya Yamashita ,  Toshiaki Tanaka ,  Shinichi Takeshima ,  Shinya Hirota ,  Eiji Iwasaki ,  Kouji Yoshizaki ,  Nobumoto Ohashi ,  Kazuhiro Itoh

发明人： Tetsuya Yamashita ,  Toshiaki Tanaka ,  Shinichi Takeshima ,  Shinya Hirota ,  Eiji Iwasaki ,  Kouji Yoshizaki ,  Nobumoto Ohashi ,  Kazuhiro Itoh

IPC分类号： F01N3/08 ,  F01N3/18 ,  F01N3/20 ,  F01N3/24 ,  F02D41/02 ,  F02D41/04 ,  F01N3/00

CPC分类号： F01N3/0842 ,  F02D41/0275 ,  F02D41/028 ,  F01N2570/04 ,  F02D2200/0806

摘要： A device for purifying the exhaust gas of an engine comprises a NO.sub.X absorbent arranged in the exhaust passage. The NO.sub.X absorbent absorbs NO.sub.X therein when the air-fuel ratio of the inflowing exhaust gas is lean, and releases the absorbed NO.sub.X therefrom when the oxygen concentration in the inflowing exhaust gas becomes lower. The NO.sub.X absorbent also absorbs SO.sub.X therein when the air-fuel ratio of the inflowing exhaust gas is lean, and releases the absorbed SO.sub.X therefrom when the oxygen concentration in the inflowing exhaust gas becomes lower, with the temperature of the NO.sub.X absorbent being higher than a SO.sub.X releasing temperature. The air-fuel ratio of the exhaust gas flowing to the NO.sub.X absorbent is made rich temporarily when the temperature of the NO.sub.X absorbent is higher than SO.sub.X releasing temperature and when the flow rate of the exhaust gas flowing through the NO.sub.X absorbent is lower than a predetermined flow rate, to release the absorbed SO.sub.X from the NO.sub.X absorbent.

摘要翻译： 用于净化发动机废气的装置包括布置在排气通道中的NO x吸收剂。 当流入的废气的空燃比是稀的时，NO x吸收剂吸收其中的NOX，并且当流入的废气中的氧浓度变低时，释放吸收的NO x。 当流入的废气的空燃比是稀的时，NOX吸收剂也吸收SO x，并且当流入废气中的氧浓度变低时，NOX吸收剂的温度高于 SOX释放温度。 当NOX吸收剂的温度高于SOX释放温度时，当流过NOX吸收剂的排气的流量低于预定的NO x吸收剂时，流入NOX吸收剂的排气的空燃比暂时变浓 流量，从NOX吸收剂中释放吸收的SOX。

公开(公告)号：US6101999A

公开(公告)日：2000-08-15

申请号：US276816

申请日：1999-03-26

申请人： Nobumoto Ohashi ,  Toshiaki Tanaka ,  Eiji Iwasaki ,  Shinya Hirota ,  Kouji Yoshizaki ,  Kazuhiro Itoh

发明人： Nobumoto Ohashi ,  Toshiaki Tanaka ,  Eiji Iwasaki ,  Shinya Hirota ,  Kouji Yoshizaki ,  Kazuhiro Itoh

IPC分类号： F02M25/07 ,  F01N3/08 ,  F01N3/20 ,  F01N3/24 ,  F02B3/06 ,  F02B47/08 ,  F02D21/08 ,  F02D41/02 ,  F02D41/04 ,  F02D41/38 ,  F02B17/00

CPC分类号： F02D41/3827 ,  F01N3/0842 ,  F02B47/08 ,  F02D41/0057 ,  F02D41/3064 ,  F02B3/06 ,  F02D2041/0022 ,  F02D2041/389 ,  F02D2200/0602 ,  F02D2250/31 ,  F02D2250/32 ,  F02D41/3845 ,  F02M26/15 ,  F02M26/23 ,  Y02T10/22 ,  Y02T10/47

摘要： A compression ignition type engine, wherein a first combustion where the amount of the recirculated exhaust gas supplied to the combustion chamber is larger than the amount of recirculated exhaust gas where the amount of production of soot peaks and almost no soot is produced and a second combustion where the amount of recirculated exhaust gas supplied to the combustion chamber is smaller than the amount of recirculated exhaust gas where the amount of production of soot peaks are selectively switched between and wherein the air-fuel ratio is temporarily made rich immediately before switching from the first combustion to the second combustion or immediately after switching from the second combustion to the first combustion.

摘要翻译： 一种压缩点火式发动机，其中，供给到所述燃烧室的再循环废气量大于产生烟灰产生量并且几乎不产生烟灰的再循环排气量的第一燃烧和第二燃烧 其中供应到燃烧室的再循环废气的量小于在其之间选择性地切换烟灰峰的产生量之间的再循环废气的量，并且其中空燃比在从第一 燃烧到第二燃烧或在从第二燃烧切换到第一燃烧之后。

公开(公告)号：US20050262829A1

公开(公告)日：2005-12-01

申请号：US11142329

申请日：2005-06-02

申请人： Kazuhiro Itoh ,  Toshiaki Tanaka ,  Eiji Iwasaki ,  Shinya Hirota

发明人： Kazuhiro Itoh ,  Toshiaki Tanaka ,  Eiji Iwasaki ,  Shinya Hirota

IPC分类号： F01N3/08 ,  B01D53/90 ,  B01D53/94 ,  C01B21/00 ,  F01N3/00 ,  F01N3/10 ,  F01N3/20 ,  F01N3/24 ,  F01N3/28 ,  F01N11/00 ,  F01N13/02 ,  F01N13/04 ,  F02D21/08 ,  F02D41/00 ,  F02D41/02 ,  F02D41/12 ,  F02M25/06 ,  F02M25/07

CPC分类号： B01D53/9409 ,  B01D53/90 ,  B01D53/9431 ,  B01D53/9495 ,  B01D2251/2062 ,  F01N3/2053 ,  F01N3/206 ,  F01N3/2066 ,  F01N3/208 ,  F01N11/002 ,  F01N13/009 ,  F01N13/0093 ,  F01N13/0097 ,  F01N13/011 ,  F01N2250/12 ,  F01N2510/063 ,  F01N2510/0682 ,  F01N2560/06 ,  F01N2570/14 ,  F01N2570/18 ,  F01N2610/02 ,  F01N2610/146 ,  F01N2900/08 ,  F01N2900/1402 ,  F01N2900/1622 ,  F02D35/025 ,  F02D41/0055 ,  F02D41/0235 ,  F02D41/123 ,  F02D41/1446 ,  F02D2200/0602 ,  F02D2200/0802 ,  F02M26/13 ,  F02M26/15 ,  Y02A50/2344 ,  Y02T10/24 ,  Y02T10/47

摘要： A catalyst (22) suitable for reduction of the NOx in an exhaust gas by ammonia in the presence of excess oxygen is arranged in the exhaust passage (18, 21) of an internal combustion engine. An aqueous urea solution is fed through a flow control valve (33) to the inside of the exhaust passage (21) upstream of the catalyst (22). When the temperature of the catalyst (22) is low, a large amount of the aqueous urea solution is fed to make the urea contained in the aqueous urea solution be stored in the catalyst (22). When the engine is accelerated and the temperature of the catalyst (22) rises, ammonia is released at a little at a time from the inside of the catalyst (22) and the NOx in the exhaust gas is reduced by the released ammonia.

公开(公告)号：US20050204729A1

公开(公告)日：2005-09-22

申请号：US11142355

申请日：2005-06-02

申请人： Kazuhiro Itoh ,  Toshiaki Tanaka ,  Eiji Iwasaki ,  Shinya Hirota

发明人： Kazuhiro Itoh ,  Toshiaki Tanaka ,  Eiji Iwasaki ,  Shinya Hirota

IPC分类号： F01N3/08 ,  B01D53/90 ,  B01D53/94 ,  C01B21/00 ,  F01N3/00 ,  F01N3/10 ,  F01N3/20 ,  F01N3/24 ,  F01N3/28 ,  F01N11/00 ,  F01N13/02 ,  F01N13/04 ,  F02D21/08 ,  F02D41/00 ,  F02D41/02 ,  F02D41/12 ,  F02M25/06 ,  F02M25/07

CPC分类号： B01D53/9409 ,  B01D53/90 ,  B01D53/9431 ,  B01D53/9495 ,  B01D2251/2062 ,  F01N3/2053 ,  F01N3/206 ,  F01N3/2066 ,  F01N3/208 ,  F01N11/002 ,  F01N13/009 ,  F01N13/0093 ,  F01N13/0097 ,  F01N13/011 ,  F01N2250/12 ,  F01N2510/063 ,  F01N2510/0682 ,  F01N2560/06 ,  F01N2570/14 ,  F01N2570/18 ,  F01N2610/02 ,  F01N2610/146 ,  F01N2900/08 ,  F01N2900/1402 ,  F01N2900/1622 ,  F02D35/025 ,  F02D41/0055 ,  F02D41/0235 ,  F02D41/123 ,  F02D41/1446 ,  F02D2200/0602 ,  F02D2200/0802 ,  F02M26/13 ,  F02M26/15 ,  Y02A50/2344 ,  Y02T10/24 ,  Y02T10/47

摘要： A catalyst (22) suitable for reduction of the NOx in an exhaust gas by ammonia in the presence of excess oxygen is arranged in the exhaust passage (18, 21) of an internal combustion engine. An aqueous urea solution is fed through a flow control valve (33) to the inside of the exhaust passage (21) upstream of the catalyst (22). When the temperature of the catalyst (22) is low, a large amount of the aqueous urea solution is fed to make the urea contained in the aqueous urea solution be stored in the catalyst (22). When the engine is accelerated and the temperature of the catalyst (22) rises, ammonia is released at a little at a time from the inside of the catalyst (22) and the NOx in the exhaust gas is reduced by the released ammonia.

公开(公告)号：US07086223B2

公开(公告)日：2006-08-08

申请号：US11142467

申请日：2005-06-02

申请人： Kazuhiro Itoh ,  Toshiaki Tanaka ,  Eiji Iwasaki ,  Shinya Hirota

发明人： Kazuhiro Itoh ,  Toshiaki Tanaka ,  Eiji Iwasaki ,  Shinya Hirota

IPC分类号： F01N3/00

CPC分类号： B01D53/9409 ,  B01D53/90 ,  B01D53/9431 ,  B01D53/9495 ,  B01D2251/2062 ,  F01N3/2053 ,  F01N3/206 ,  F01N3/2066 ,  F01N3/208 ,  F01N11/002 ,  F01N13/009 ,  F01N13/0093 ,  F01N13/0097 ,  F01N13/011 ,  F01N2250/12 ,  F01N2510/063 ,  F01N2510/0682 ,  F01N2560/06 ,  F01N2570/14 ,  F01N2570/18 ,  F01N2610/02 ,  F01N2610/146 ,  F01N2900/08 ,  F01N2900/1402 ,  F01N2900/1622 ,  F02D35/025 ,  F02D41/0055 ,  F02D41/0235 ,  F02D41/123 ,  F02D41/1446 ,  F02D2200/0602 ,  F02D2200/0802 ,  F02M26/13 ,  F02M26/15 ,  Y02A50/2344 ,  Y02T10/24 ,  Y02T10/47

摘要： A catalyst (22) suitable for reduction of the NOx in an exhaust gas by ammonia in the presence of excess oxygen is arranged in the exhaust passage (18, 21) of an internal combustion engine. An aqueous urea solution is fed through a flow control valve (33) to the inside of the exhaust passage (21) upstream of the catalyst (22). When the temperature of the catalyst (22) is low, a large amount of the aqueous urea solution is fed to make the urea contained in the aqueous urea solution be stored in the catalyst (22). When the engine is accelerated and the temperature of the catalyst (22) rises, ammonia is released at a little at a time from the inside of the catalyst (22) and the NOx in the exhaust gas is reduced by the released ammonia.

摘要翻译： 在内燃机的排气通道（18,21）中布置有适合于在过量氧气存在下用氨还原废气中的NO x的催化剂（22）。 尿素水溶液通过流量控制阀（33）进入催化剂（22）上游的排气通道（21）的内部。 当催化剂（22）的温度低时，进料大量的尿素水溶液使尿素水溶液中所含的尿素储存在催化剂（22）中。 当发动机加速并且催化剂（22）的温度上升时，氨从催化剂（22）的内部一次释放，排气中的NO x x 由释放的氨减少。

公开(公告)号：US06959540B2

公开(公告)日：2005-11-01

申请号：US10943946

申请日：2004-09-20

申请人： Kazuhiro Itoh ,  Toshiaki Tanaka ,  Eiji Iwasaki ,  Shinya Hirota

发明人： Kazuhiro Itoh ,  Toshiaki Tanaka ,  Eiji Iwasaki ,  Shinya Hirota

IPC分类号： F01N3/08 ,  B01D53/90 ,  B01D53/94 ,  C01B21/00 ,  F01N3/00 ,  F01N3/10 ,  F01N3/20 ,  F01N3/24 ,  F01N3/28 ,  F01N11/00 ,  F01N13/02 ,  F01N13/04 ,  F02D21/08 ,  F02D41/00 ,  F02D41/02 ,  F02D41/12 ,  F02M25/06 ,  F02M25/07

CPC分类号： B01D53/9409 ,  B01D53/90 ,  B01D53/9431 ,  B01D53/9495 ,  B01D2251/2062 ,  F01N3/2053 ,  F01N3/206 ,  F01N3/2066 ,  F01N3/208 ,  F01N11/002 ,  F01N13/009 ,  F01N13/0093 ,  F01N13/0097 ,  F01N13/011 ,  F01N2250/12 ,  F01N2510/063 ,  F01N2510/0682 ,  F01N2560/06 ,  F01N2570/14 ,  F01N2570/18 ,  F01N2610/02 ,  F01N2610/146 ,  F01N2900/08 ,  F01N2900/1402 ,  F01N2900/1622 ,  F02D35/025 ,  F02D41/0055 ,  F02D41/0235 ,  F02D41/123 ,  F02D41/1446 ,  F02D2200/0602 ,  F02D2200/0802 ,  F02M26/13 ,  F02M26/15 ,  Y02A50/2344 ,  Y02T10/24 ,  Y02T10/47

摘要： A catalyst (22) suitable for reduction of the NOx in an exhaust gas by ammonia in the presence of excess oxygen is arranged in the exhaust passage (18, 21) of an internal combustion engine. An aqueous urea solution is fed through a flow control valve (33) to the inside of the exhaust passage (21) upstream of the catalyst (22). When the temperature of the catalyst (22) is low, a large amount of the aqueous urea solution is fed to make the urea contained in the aqueous urea solution be stored in the catalyst (22). When the engine is accelerated and the temperature of the catalyst (22) rises, ammonia is released at a little at a time from the inside of the catalyst (22) and the NOx in the exhaust gas is reduced by the released ammonia.

摘要翻译： 在内燃机的排气通道（18,21）中布置有适合于在过量氧气存在下用氨还原废气中的NO x的催化剂（22）。 尿素水溶液通过流量控制阀（33）进入催化剂（22）上游的排气通道（21）的内部。 当催化剂（22）的温度低时，进料大量的尿素水溶液使尿素水溶液中所含的尿素储存在催化剂（22）中。 当发动机加速并且催化剂（22）的温度上升时，氨从催化剂（22）的内部一次释放，排气中的NO x x 由释放的氨减少。

公开(公告)号：US20050217248A1

公开(公告)日：2005-10-06

申请号：US11142242

申请日：2005-06-02

申请人： Kazuhiro Itoh ,  Toshiaki Tanaka ,  Eiji Iwasaki ,  Shinya Hirota

发明人： Kazuhiro Itoh ,  Toshiaki Tanaka ,  Eiji Iwasaki ,  Shinya Hirota

IPC分类号： F01N3/08 ,  B01D53/90 ,  B01D53/94 ,  C01B21/00 ,  F01N3/00 ,  F01N3/10 ,  F01N3/20 ,  F01N3/24 ,  F01N3/28 ,  F01N11/00 ,  F01N13/02 ,  F01N13/04 ,  F02D21/08 ,  F02D41/00 ,  F02D41/02 ,  F02D41/12 ,  F02M25/06 ,  F02M25/07

CPC分类号： B01D53/9409 ,  B01D53/90 ,  B01D53/9431 ,  B01D53/9495 ,  B01D2251/2062 ,  F01N3/2053 ,  F01N3/206 ,  F01N3/2066 ,  F01N3/208 ,  F01N11/002 ,  F01N13/009 ,  F01N13/0093 ,  F01N13/0097 ,  F01N13/011 ,  F01N2250/12 ,  F01N2510/063 ,  F01N2510/0682 ,  F01N2560/06 ,  F01N2570/14 ,  F01N2570/18 ,  F01N2610/02 ,  F01N2610/146 ,  F01N2900/08 ,  F01N2900/1402 ,  F01N2900/1622 ,  F02D35/025 ,  F02D41/0055 ,  F02D41/0235 ,  F02D41/123 ,  F02D41/1446 ,  F02D2200/0602 ,  F02D2200/0802 ,  F02M26/13 ,  F02M26/15 ,  Y02A50/2344 ,  Y02T10/24 ,  Y02T10/47

摘要： A catalyst (22) suitable for reduction of the NOx in an exhaust gas by ammonia in the presence of excess oxygen is arranged in the exhaust passage (18, 21) of an internal combustion engine. An aqueous urea solution is fed through a flow control valve (33) to the inside of the exhaust passage (21) upstream of the catalyst (22). When the temperature of the catalyst (22) is low, a large amount of the aqueous urea solution is fed to make the urea contained in the aqueous urea solution be stored in the catalyst (22). When the engine is accelerated and the temperature of the catalyst (22) rises, ammonia is released at a little at a time from the inside of the catalyst (22) and the NOx in the exhaust gas is reduced by the released ammonia.

公开(公告)号：US20050034450A1

公开(公告)日：2005-02-17

申请号：US10943946

申请日：2004-09-20

申请人： Kazuhiro Itoh ,  Toshiaki Tanaka ,  Eiji Iwasaki ,  Shinya Hirota

发明人： Kazuhiro Itoh ,  Toshiaki Tanaka ,  Eiji Iwasaki ,  Shinya Hirota

IPC分类号： F01N3/08 ,  B01D53/90 ,  B01D53/94 ,  C01B21/00 ,  F01N3/00 ,  F01N3/10 ,  F01N3/20 ,  F01N3/24 ,  F01N3/28 ,  F01N11/00 ,  F01N13/02 ,  F01N13/04 ,  F02D21/08 ,  F02D41/00 ,  F02D41/02 ,  F02D41/12 ,  F02M25/06 ,  F02M25/07 ,  C01B35/00 ,  B01J8/02

CPC分类号： B01D53/9409 ,  B01D53/90 ,  B01D53/9431 ,  B01D53/9495 ,  B01D2251/2062 ,  F01N3/2053 ,  F01N3/206 ,  F01N3/2066 ,  F01N3/208 ,  F01N11/002 ,  F01N13/009 ,  F01N13/0093 ,  F01N13/0097 ,  F01N13/011 ,  F01N2250/12 ,  F01N2510/063 ,  F01N2510/0682 ,  F01N2560/06 ,  F01N2570/14 ,  F01N2570/18 ,  F01N2610/02 ,  F01N2610/146 ,  F01N2900/08 ,  F01N2900/1402 ,  F01N2900/1622 ,  F02D35/025 ,  F02D41/0055 ,  F02D41/0235 ,  F02D41/123 ,  F02D41/1446 ,  F02D2200/0602 ,  F02D2200/0802 ,  F02M26/13 ,  F02M26/15 ,  Y02A50/2344 ,  Y02T10/24 ,  Y02T10/47

摘要： A catalyst (22) suitable for reduction of the NOx in an exhaust gas by ammonia in the presence of excess oxygen is arranged in the exhaust passage (18, 21) of an internal combustion engine. An aqueous urea solution is fed through a flow control valve (33) to the inside of the exhaust passage (21) upstream of the catalyst (22). When the temperature of the catalyst (22) is low, a large amount of the aqueous urea solution is fed to make the urea contained in the aqueous urea solution be stored in the catalyst (22). When the engine is accelerated and the temperature of the catalyst (22) rises, ammonia is released at a little at a time from the inside of the catalyst (22) and the NOx in the exhaust gas is reduced by the released ammonia.

摘要翻译： 在内燃机的排气通道（18,21）中设置适于在过量氧气存在下用氨还原废气中的NOx的催化剂（22）。 尿素水溶液通过流量控制阀（33）进入催化剂（22）上游的排气通道（21）的内部。 当催化剂（22）的温度低时，进料大量的尿素水溶液使尿素水溶液中所含的尿素储存在催化剂（22）中。 当发动机被加速并且催化剂（22）的温度升高时，氨从催化剂（22）的内部一次释放，并且废气中的NOx被释放的氨降低。