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公开(公告)号:US5746052A
公开(公告)日:1998-05-05
申请号:US525892
申请日:1995-09-08
CPC分类号: B01D53/9454 , B01D53/9431 , B01D53/9477 , B01D53/9495 , F01N13/009 , F01N13/011 , F01N3/20 , F01N3/206 , F01N2240/25 , F01N2570/14 , F01N2610/02 , Y02T10/22
摘要: In the present invention, the exhaust gas from the engine is divided into a first and a second branch exhaust passages after it passes through a three-way reducing and oxidizing catalyst, and the two branch exhaust passages merge into an exhaust gas outlet passage. In the first branch exhaust passage, an oxidizing catalyst is disposed, and in the exhaust gas outlet passage, a denitrating and oxidizing catalyst is disposed. NO.sub.x in the exhaust gas from the engine is all converted to N.sub.2 and NH.sub.3 by the three-way reducing and oxidizing catalyst and a part of the NH.sub.3 generated by the three-way catalyst flows into the first branch exhaust passage and is converted to NO.sub.x again by the oxidizing catalyst. The amount of NO.sub.x produced by the oxidizing catalyst and the amount of NO.sub.x flowing through the second branch exhaust passage is determined by the flow distribution ratio of the first and the second branch exhaust passages. In this invention, the flow ratio is determined in such a manner that the amount of the NO.sub.x produced by the oxidizing catalyst and the amount of the NH.sub.3 passing through the second branch exhaust passage are stoichiometric to produce N.sub.2 and H.sub.2 O. Therefore, when these exhaust gases flow into the denitrating and oxidizing catalyst after they mix with each other in the exhaust gas outlet passage, all the NO.sub.x and the NH.sub.3 are converted to N.sub.2 and H.sub.2 O by the denitrating and oxidizing catalyst without producing any surplus NO.sub.x or NH.sub.3.
摘要翻译: 在本发明中,来自发动机的废气在通过三通还原氧化催化剂后被分成第一和第二分支排气通道,两个分支排气通道合流到废气出口通道中。 在第一分支排气通道中设置氧化催化剂,并且在排气出口通道中设置脱硝和氧化催化剂。 来自发动机的废气中的NOx通过三元还原氧化催化剂全部转化为N 2和NH 3,并且由三元催化剂产生的一部分NH 3流入第一分支排气通道并再次转化为NOx 通过氧化催化剂。 由氧化催化剂产生的NOx的量和流过第二分支排气通道的NOx的量由第一和第二分支排气通道的流量分配比确定。 在本发明中,流量比以如下方式确定:氧化催化剂产生的NOx的量和通过第二分支排气通道的NH 3的量是化学计量的,以产生N 2和H 2 O. 因此,当这些废气在废气出口通道中彼此混合后流入脱硝和氧化催化剂时,所有的NOx和NH 3都被脱硝和氧化催化剂转化为N 2和H 2 O,而不产生任何剩余的NOx或 NH3。
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公开(公告)号:US6133185A
公开(公告)日:2000-10-17
申请号:US744814
申请日:1996-11-06
申请人: Yukio Kinugasa , Kouhei Igarashi , Takaaki Itou , Naoto Suzuki , Takehisa Yaegashi , Takaaki Kanazawa , Takahiro Hayashi , Koji Yokota , Yasutaka Nagai
发明人: Yukio Kinugasa , Kouhei Igarashi , Takaaki Itou , Naoto Suzuki , Takehisa Yaegashi , Takaaki Kanazawa , Takahiro Hayashi , Koji Yokota , Yasutaka Nagai
CPC分类号: F01N3/10 , B01D53/9418 , B01D53/9495 , F01N13/009 , F01N13/0097 , F01N3/0842 , F01N3/106 , F01N3/108 , B01D2255/1021 , B01D2255/20761 , B01D2255/50 , B01D2255/911 , B01D53/9477 , F01N2240/25 , F01N2250/12 , F01N2370/04 , F01N2570/14 , F02B1/04 , F02D41/0275 , Y02T10/24
摘要: An exhaust gas purifying catalyst, for reducing nitrogen oxides and ammonia in an exhaust gas of an internal combustion engine, in an oxidizing atmosphere, is provided. The exhaust gas purifying catalyst comprises a first catalyst having zeolite carrying platinum and copper thereon. Preferably, the exhaust gas purifying catalyst further comprises a second catalyst having zeolite carrying copper thereon. Preferably, the second catalyst is arranged upstream of the first catalyst, with respect to the exhaust gas flow.
摘要翻译: 提供一种用于在氧化气氛中还原内燃机的废气中的氮氧化物和氨的废气净化催化剂。 废气净化催化剂包括具有在其上载有铂和铜的沸石的第一催化剂。 优选地,废气净化催化剂还包含具有在其上载有铜的沸石的第二催化剂。 优选地,第二催化剂相对于废气流布置在第一催化剂的上游。
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公开(公告)号:US5964088A
公开(公告)日:1999-10-12
申请号:US822555
申请日:1997-03-19
申请人: Yukio Kinugasa , Takaaki Itou , Koichi Hoshi , Naoto Suzuki , Koichi Takeuchi , Takehisa Yaegashi , Kouhei Igarashi
发明人: Yukio Kinugasa , Takaaki Itou , Koichi Hoshi , Naoto Suzuki , Koichi Takeuchi , Takehisa Yaegashi , Kouhei Igarashi
IPC分类号: F02D43/00 , B01D53/94 , F01N3/08 , F01N3/20 , F01N3/24 , F01N9/00 , F01N13/02 , F02B1/04 , F02D41/02 , F02D41/04 , F02D41/14 , F01N3/00
CPC分类号: F02D41/1443 , B01D53/9431 , B01D53/9495 , F01N13/009 , F01N3/0842 , F01N3/0871 , F01N3/20 , F01N9/00 , F01N2240/25 , F01N2250/12 , F01N2560/025 , F01N2560/06 , F01N2610/02 , F01N2610/03 , F02B1/04 , F02D41/0275 , Y02T10/22 , Y02T10/42 , Y02T10/47
摘要: A device for purifying the exhaust gas of an engine having a plurality of cylinders divided into first and second cylinder groups, the first and the second cylinder groups being connected to first and second exhaust passage, respectively, and performing a lean operation, comprises an NH.sub.3 synthesizing catalyst arranged in the first exhaust passage, and an exhaust gas purifying catalyst arranged in an interconnecting passage, which interconnects the first passage downstream of the NH.sub.3 synthesizing catalyst and the second exhaust passage, for purifying the inflowing NO.sub.X and NH.sub.3. An additional engine performing a rich operation is provided and the exhaust gas thereof is fed to the first exhaust gas passage upstream of the NH.sub.3 synthesizing catalyst to make the exhaust gas air-fuel ratio of the exhaust gas flowing into the NH.sub.3 synthesizing catalyst rich, to thereby synthesize NH.sub.3 therein. An amount of NH.sub.3 or NO.sub.X flowing into the exhaust gas purifying catalyst is obtained, and the additional engine is controlled in accordance with the obtained NH.sub.3 or NO.sub.X amount to control the amount of the reducing agent flowing to the exhaust gas purifying catalyst.
摘要翻译: 一种用于净化具有分成第一和第二气缸组的多个气缸的发动机的排气的装置,所述第一和第二气缸组分别连接到第一和第二排气通道,并执行精馏操作,包括NH 3 配置在第一排气通道中的合成催化剂和布置在互连通道中的排气净化催化剂,其将NH3合成催化剂下游的第一通道和第二排气通道互连,以净化流入的NO x和NH 3。 提供执行富操作的附加发动机,其排气被送入NH 3合成催化剂上游的第一排气通道,使流入NH 3合成催化剂的废气的排气空燃比变浓,至 由此合成NH 3。 获得流入排气净化催化剂的NH 3或NO X量,根据得到的NH 3或NO X量控制附加发动机,以控制流向废气净化催化剂的还原剂的量。
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公开(公告)号:US6047542A
公开(公告)日:2000-04-11
申请号:US68422
申请日:1998-06-29
申请人: Yukio Kinugasa , Kouhei Igarashi , Takaaki Itou , Naoto Suzuki , Takehisa Yaegashi , Kouichi Takeuchi
发明人: Yukio Kinugasa , Kouhei Igarashi , Takaaki Itou , Naoto Suzuki , Takehisa Yaegashi , Kouichi Takeuchi
IPC分类号: F02D43/00 , B01D53/86 , B01D53/94 , B01J23/40 , B01J23/70 , B01J29/04 , F01N3/08 , F01N3/10 , F01N3/20 , F01N3/24 , F01N3/28 , F01N13/02 , F01N13/04 , F02B1/04 , F02D41/02 , F02D41/04 , F02D41/14 , F01N3/00
CPC分类号: F01N3/2073 , B01D53/8696 , B01D53/9431 , B01D53/9495 , F01N13/009 , F01N13/011 , F01N13/107 , F01N3/0842 , F01N3/0871 , F01N3/20 , F01N3/2053 , F02D41/027 , F02D41/1443 , F02D41/1475 , F01N2240/25 , F01N2250/12 , F01N2610/02 , F02B1/04 , F02D41/0275 , Y02T10/22
摘要: An engine (1) has first and second cylinder groups (1a) and (1b). The first cylinder group (1a) is connected to a three way (TW) catalyst (8a). The second group (1b) and the TW catalyst (8a) are connected, via an interconnecting duct (13) to an NH.sub.3 adsorbing and oxidizing (NH.sub.3 -AO) catalyst (14a). The first group (1a) performs the rich operation, and the second group (1b) performs the lean operation. In the TW catalyst (8a), NO.sub.x exhausted from the first group (1a) is converted to NH.sub.3, and the NH.sub.3 reduces the NO.sub.x exhausted from the second group (1b) in the NH.sub.3 -AO catalyst (14a). A NO.sub.x occluding and reducing (NO.sub.x -OR) catalyst (11a) is arranged in the exhaust passage between the second group (1b) and the interconnecting duct (13), to thereby suppress the NO.sub.x amount flowing into the NH.sub.3 -AO catalyst (14a).
摘要翻译: PCT No.PCT / JP96 / 03332 Sec。 371日期1998年6月29日第 102(e)1998年6月29日PCT PCT 1996年11月13日PCT公布。 公开号WO97 / 19262 日期1997年5月29日发动机(1)具有第一和第二气缸组(1a)和(1b)。 第一气缸组(1a)连接到三通(TW)催化剂(8a)。 第二组(1b)和TW催化剂(8a)通过互连导管(13)连接到NH 3吸附和氧化(NH3-AO)催化剂(14a)。 第一组(1a)执行丰富操作,第二组(1b)执行精简操作。 在TW催化剂(8a)中,从第一组(1a)排出的NOx转化为NH 3,并且NH 3减少在NH3-AO催化剂(14a)中从第二组(1b)排出的NOx。 在第二组(1b)和互连管(13)之间的排气通道中设置有NOx吸留还原(NOx-OR)催化剂(11a),从而抑制流入NH 3 -A AO催化剂(14a)的NOx量 )。
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公开(公告)号:US5782087A
公开(公告)日:1998-07-21
申请号:US746056
申请日:1996-11-06
申请人: Yukio Kinugasa , Kouhei Igarashi , Takaaki Itou , Naoto Suzuki , Takehisa Yaegashi , Toshiaki Tanaka
发明人: Yukio Kinugasa , Kouhei Igarashi , Takaaki Itou , Naoto Suzuki , Takehisa Yaegashi , Toshiaki Tanaka
IPC分类号: F02D45/00 , B01D53/86 , B01D53/94 , F01N3/08 , F01N3/20 , F01N3/24 , F01N3/28 , F01N9/00 , F01N13/02 , F02B1/04 , F02D41/04
CPC分类号: F01N3/0842 , B01D53/9409 , B01D53/9436 , B01D53/9495 , F01N13/009 , F01N3/0871 , F01N3/20 , F01N9/00 , F01N2250/12 , F01N2370/04 , F02B1/04 , Y02T10/22 , Y02T10/47
摘要: An exhaust manifold of an engine is connected to a three way (TW) catalyst, and the TW catalyst is connected to an NH.sub.3 adsorbing and oxidizing (NH.sub.3 -AO) catalyst, such as the Cu-zeolite catalyst. The engine performs the lean and the rich operations alternately and repeatedly. When the engine performs the rich operation, the TW catalyst synthesizes NH.sub.3 from NO.sub.x in the inflowing exhaust gas, and the NH.sub.3 is then adsorbed in the NH.sub.3 -AO catalyst. Next, when the engine performs the lean operation, NO.sub.x passes through the TW catalyst, and the adsorbed NH.sub.3 is desorbed and reduces the inflowing NO.sub.x. When the rich operation is in process, or is to be started, the exhaust gas temperature flowing into the NH.sub.3 -AO catalyst is detected. If the temperature is equal to or higher than the upper threshold representing the rich endurance temperature, the lean or the stoichiometric operation is performed.
摘要翻译: 发动机的排气歧管连接到三通(TW)催化剂,TW催化剂连接到NH 3吸附和氧化(NH3-AO)催化剂如Cu-沸石催化剂上。 发动机交替重复执行精益和丰富的操作。 当发动机进行浓缩操作时,TW催化剂在流入的废气中从NOx合成NH 3,然后NH 3被吸附在NH3-AO催化剂中。 接下来,当发动机进行稀薄运转时,NOx通过TW催化剂,吸附的NH 3被解吸并减少流入的NOx。 当富运行正在进行或正在启动时,检测流入NH3-AO催化剂的废气温度。 如果温度等于或高于表示富耐久温度的上限阈值,则执行稀薄或化学计量操作。
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公开(公告)号:US06345496B1
公开(公告)日:2002-02-12
申请号:US09502127
申请日:2000-02-10
申请人: Naohide Fuwa , Hiroshi Tanaka , Yukio Kinugasa , Takaaki Itou , Naoto Suzuki , Takehisa Yaegashi , Kouhei Igarashi , Kouichi Takeuchi
发明人: Naohide Fuwa , Hiroshi Tanaka , Yukio Kinugasa , Takaaki Itou , Naoto Suzuki , Takehisa Yaegashi , Kouhei Igarashi , Kouichi Takeuchi
IPC分类号: F01N300
CPC分类号: F02D41/1475 , B01D53/8696 , B01D53/9409 , B01D53/9422 , B01D53/9431 , B01D53/9445 , B01D53/9454 , B01D53/9477 , B01D53/9495 , B01D2255/102 , B01D2255/20761 , B01D2255/50 , B01D2255/911 , F01N3/0842 , F01N3/0871 , F01N3/20 , F01N3/2053 , F01N9/00 , F01N13/009 , F01N13/011 , F01N13/107 , F01N2240/25 , F01N2250/12 , F01N2570/18 , F01N2610/02 , F01N2610/03 , F02B1/04 , F02D41/027 , F02D41/0275 , F02D41/1443 , Y02T10/22 , Y02T10/24 , Y02T10/47
摘要: An exhaust manifold (7) of an engine (1) is connected to a three way (TW) catalyst (8a), and the TW catalyst (8a) is connected to an NH3 adsorbing and oxidizing (NH3-AO) catalyst (10a). The engine (1) performs the lean and the rich engine operations alternately and repeatedly. When the engine (1) performs the rich operation and thereby the exhaust gas air-fuel ratio of the exhaust gas flowing into the TW catalyst (8a) is made rich, NOx in the inflowing exhaust gas is converted to NH3 in the TW catalyst (8a). The NH3 is then adsorbed in the NH3-AO catalyst (10a). Next, when the engine (1) performs the lean operation and thereby the exhaust gas air-fuel ratio of the exhaust gas flowing into the TW catalyst (8a) is made lean, NOx in the exhausted gas passes through the TW catalyst (8a), and flows into the NH3-AO catalyst (10a). At this time, NH3 adsorbed in the catalyst (10a) is desorbed therefrom, and reduces the inflowing NOx.
摘要翻译: 发动机(1)的排气歧管(7)与三通(TW)催化剂(8a)连接,TW催化剂(8a)与NH3吸附和氧化(NH3-AO)催化剂(10a)连接, 。 发动机(1)交替地重复执行精益和丰富的发动机操作。 当发动机(1)进行浓作操作,使流入TW催化剂(8a)的废气的排气空燃比变浓时,在TW催化剂中将流入废气中的NOx转化成NH 3 8a)。 然后将NH 3吸附在NH3-AO催化剂(10a)中。 接下来,当发动机(1)进行稀薄运转,从而将流入TW催化剂(8a)的废气的排气空燃比变为稀薄时,排出气体中的NOx通过TW催化剂(8a) 并流入NH3-AO催化剂(10a)。 此时,吸附在催化剂(10a)中的NH 3被脱附,并且减少了流入的NOx。
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公开(公告)号:US6119452A
公开(公告)日:2000-09-19
申请号:US68684
申请日:1998-05-13
申请人: Yukio Kinugasa , Kouhei Igarashi , Takaaki Itou , Naoto Suzuki , Takehisa Yaegashi , Toshiaki Tanaka , Naoto Miyoshi
发明人: Yukio Kinugasa , Kouhei Igarashi , Takaaki Itou , Naoto Suzuki , Takehisa Yaegashi , Toshiaki Tanaka , Naoto Miyoshi
IPC分类号: B01D53/86 , B01D53/94 , F01N3/08 , F01N3/20 , F01N13/02 , F01N13/04 , F02B1/04 , F02D41/02 , F02D41/14 , F01N3/00
CPC分类号: F01N3/2073 , B01D53/8696 , B01D53/9431 , B01D53/9454 , B01D53/9495 , F01N13/009 , F01N13/011 , F01N3/0842 , F01N3/0871 , F01N3/20 , F01N3/2053 , F02D41/027 , F02D41/1443 , F02D41/1475 , F01N2240/25 , F01N2250/12 , F01N2610/02 , F02B1/04 , F02D41/0275 , Y02T10/22
摘要: A three-way catalyst (8a) is connected to a first cylinder group 1a. The exhaust gas of the first cylinder group (1a), which has passed through the three-way catalyst (8a), and the exhaust gas of a second cylinder group (1b) are introduced to an exhaust gas purifying catalyst (14). The second cylinder group (1b) performs the lean operation. The first cylinder group (1a) performs the rich operation to synthesize NH.sub.3 from NO.sub.X in the exhaust gas of the first cylinder group (1a) in the three-way catalyst (8a). In the exhaust gas purifying catalyst (14), NO.sub.X in the exhaust gas of the second cylinder group 1b is purified by NH.sub.3 from the three-way catalyst (8a). The amount of HC flowing to the three-way catalyst (8a) is obtained. When the HC amount exceeds a predetermined amount, the first cylinder group 1a must perform the lean operation temporarily, to thereby maintain the excellent catalytic activity of the three-way catalyst (8a).
摘要翻译: PCT No.PCT / JP96 / 03288 Sec。 371日期1998年5月13日 102(e)日期1998年5月13日PCT 1996年11月8日PCT PCT。 公开号WO97 / 19261 日期1997年5月29日将三元催化剂(8a)连接到第一气缸组1a。 已经通过三元催化剂(8a)的第一气缸组(1a)的排气和第二气缸组(1b)的排气被引入废气净化催化剂(14)。 第二气缸组(1b)执行精馏操作。 第一气缸组(1a)在三元催化剂(8a)中进行第一气缸组(1a)的排气中的NO x的富NH操作。 在排气净化催化剂(14)中,第三气缸组1b的废气中的NO x从三元催化剂(8a)中被NH 3净化。 获得流向三元催化剂(8a)的HC量。 当HC量超过预定量时,第一气缸组1a必须暂时进行稀薄运转,从而保持三元催化剂(8a)的极好的催化活性。
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公开(公告)号:US5740669A
公开(公告)日:1998-04-21
申请号:US559107
申请日:1995-11-16
IPC分类号: F02D45/00 , B01D53/56 , B01D53/81 , B01D53/86 , B01D53/94 , F01N3/08 , F01N3/18 , F01N3/30 , F01N9/00 , F01N13/02 , F02D41/02 , F02D41/04 , F02D41/14 , F01N3/28
CPC分类号: F01N3/0842 , F01N13/009 , F01N3/0871 , F01N3/30 , F01N9/00 , F02D41/0275 , F01N2240/18 , F01N2390/02 , F01N2430/06 , F02D2200/0802 , Y02C20/10 , Y02T10/47
摘要: In the present invention, a NO.sub.x absorbent is used for removing the NO.sub.x in the exhaust gas. The NO.sub.x absorbent absorbs NO.sub.x in the exhaust gas when the air-fuel ratio of the exhaust gas is lean, and releases the absorbed NO.sub.x and reduces it to nitrogen when the air-fuel ratio of the exhaust gas is rich or stoichiometric. To prevent the NO.sub.x absorbent from being saturated with the absorbed NO.sub.x, the NO.sub.x absorbent must be regenerated periodically by causing the NO.sub.x in the absorbent to be released and reduced. However, it is found that when the regenerating process by supplying a rich air-fuel ratio exhaust gas to the NO.sub.x absorbent is carried out at high NO.sub.x absorbent temperature, a part of NO.sub.x flows out from the NO.sub.x absorbent at the beginning of the regenerating process without being reduced. In the present invention, this outflow of NO.sub.x is suppressed by, for example, carrying out the regenerating process only when the temperature of the NO.sub.x absorbent is lowered to a predetermined temperature. This predetermined temperature is set low enough to ensure that the amount of the outflow of NO.sub.x is minimized.
摘要翻译: 在本发明中,使用NOx吸收剂除去废气中的NOx。 当排气的空燃比稀薄时,NOx吸收剂吸收废气中的NOx,并且当排气的空燃比浓或化学计量时,释放吸收的NOx并将其还原成氮。 为了防止NOx吸收剂被吸收的NOx饱和,NOx吸收剂必须通过使吸收剂中的NOx释放和还原而周期性地再生。 然而,发现当在高NOx吸收温度下进行通过向NOx吸收剂供给浓空燃比废气的再生过程时,在再生过程开始时,部分NOx从NOx吸收剂流出 没有减少 在本发明中,只有当NOx吸收剂的温度下降到规定温度时,例如仅进行再生处理,可以抑制NOx的流出。 该预定温度被设定得足够低以确保NOx的流出量最小化。
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公开(公告)号:US06409973B1
公开(公告)日:2002-06-25
申请号:US08523455
申请日:1995-09-05
IPC分类号: B01D5314
CPC分类号: B01D53/9481 , B01D53/9495 , F01N3/0842 , F01N3/0871 , F01N3/0878 , F01N3/22 , F01N13/011 , F01N2270/00 , F01N2410/12 , F01N2610/03 , F01N2610/04 , F02B1/04
摘要: The exhaust gas purification device according to the present invention utilizes two NOx absorbents in order to remove NOx from the exhaust gas of an engine operated at a lean air-fuel ratio. The NOx absorbents are disposed, in series, in the exhaust passage of the engine and a nozzle for supplying a reducing agent is disposed in the exhaust passage at a position between the two NOx absorbents. Further, the device includes switching valves for changing the direction of the exhaust gas flow in the exhaust gas passage. When the switching valves are set to direct the exhaust gas flow to one direction, the exhaust gas first flows through one of the NOx absorbents (first NOx absorbent), and after passing through the first NOx absorbent, the reducing agent is supplied to the exhaust gas before it flows into the other NOx absorbent (second NOx absorbent). Thus, the first NOx absorbent absorbs NOx in the exhaust gas, and the NOx absorbed by the second NOabsorbent is released from the second NOx absorbent. When the switching valves are switched, the exhaust gas flows in the opposite direction, and flows through the second NOx absorbent and the first NOx absorbent in this order. In this case, the second NOx absorbent absorbs NOx in the exhaust gas, and the NOx absorbed by the first NOx absorbent is released and reduced to N2. Therefore, by reversing the direction of the exhaust gas periodically, the absorbing operation of NOx and releasing/reducing operation of NOx are performed by two NOx absorbents alternately. Thus, it becomes possible to remove NOx in the exhaust gas continuously while the NOx absorbents are prevented from being saturated by the absorbed NOx.
摘要翻译: 根据本发明的排气净化装置利用两个NOx吸收剂来从以稀空燃比运转的发动机的废气中除去NOx。 NOx吸收剂串联设置在发动机的排气通道中,并且用于供给还原剂的喷嘴设置在排气通道中的两个NOx吸收剂之间的位置。 此外,该装置包括用于改变排气通道中的排气流的方向的切换阀。 当切换阀被设定为将废气流引导到一个方向时,废气首先流过NOx吸收剂之一(第一NOx吸收剂),并且在通过第一NOx吸收剂之后,还原剂被供给到排气 气体在其流入另一个NOx吸收剂(第二NOx吸收剂)之前。 因此,第一NOx吸收剂吸收废气中的NOx,并且由第二NO吸收剂吸收的NOx从第二NOx吸收剂释放。 当切换阀切换时,排气沿相反方向流动,并且依次流过第二NOx吸收剂和第一NOx吸收剂。 在这种情况下,第二NOx吸收剂吸收废气中的NOx,并且由第一NOx吸收剂吸收的NOx被释放并且还原成N2。 因此,通过周期性地反转排气的方向,NOx的吸收运转和NOx的释放/还原运转由两个NOx吸收剂交替进行。 因此,可以连续地除去排气中的NOx,同时防止NOx吸收剂被吸收的NOx饱和。
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公开(公告)号:US5783160A
公开(公告)日:1998-07-21
申请号:US590714
申请日:1996-01-24
申请人: Yukio Kinugasa , Kouhei Igarashi , Takaaki Itou , Toshifumi Takaoka , Michihiro Ohashi , Koji Yokota
发明人: Yukio Kinugasa , Kouhei Igarashi , Takaaki Itou , Toshifumi Takaoka , Michihiro Ohashi , Koji Yokota
CPC分类号: B01D53/9481 , B01D53/9409 , B01D53/9436 , B01D53/9495 , F01N13/009 , F01N3/0842 , F01N3/0871 , F01N3/206 , F01N3/22 , F01N3/222 , F01N2230/04 , F01N2240/25 , F01N2250/12 , F01N2610/02 , Y02T10/22
摘要: The method for purifying combustion exhaust gas according to the present invention utilizes a NH.sub.3 decomposing catalyst. The NH.sub.3 decomposing catalyst in the present invention is capable of converting substantially all of the NH.sub.3 in the combustion exhaust gas to N.sub.2 when the air-fuel ratio of the exhaust gas is lean and the temperature of the catalyst is within a predetermined optimum temperature range. Further, when the exhaust gas contains NO.sub.x in addition to NH.sub.3, the NH.sub.3 decomposing catalyst is capable of reducing the NO.sub.x in the optimum temperature range even though the air-fuel ratio of the exhaust gas is lean. In the present invention, the conditions of the exhaust gas containing NO.sub.x are adjusted before it is fed to the NH.sub.3 decomposing catalyst in such a manner that the temperature of the exhaust gas is within the optimum temperature range and the air-fuel ratio of the exhaust gas is lean. Further, NH.sub.3 is added to the exhaust gas before it is fed to the NH.sub.3 decomposing catalyst. Therefore, a lean air-fuel ratio exhaust gas, at a temperature within the optimum temperature range, which contains both the NO.sub.x and NH.sub.3 is fed to the NH.sub.3 decomposing catalyst, and the NO.sub.x, as well as the NH.sub.3, in the exhaust gas is completely resolved by the NH.sub.3 decomposing catalyst.
摘要翻译: 根据本发明的用于净化燃烧废气的方法利用NH 3分解催化剂。 本发明中的NH 3分解催化剂能够在排气的空燃比稀薄且催化剂的温度在预定的最佳温度范围内时将燃烧废气中的NH 3基本上全部转化成N2。 此外,当排气中含有除NH 3之外的NOx时,NH 3分解催化剂即使在排气的空燃比较稀的情况下也能够将NOx还原到最佳温度范围。 在本发明中,在将废气的温度设定在最佳温度范围内并排气的空燃比的方式调节含有NOx的废气的条件,然后送入NH 3分解催化剂 气体很瘦 此外,在将其输入到NH 3分解催化剂之前,将NH 3加入到废气中。 因此,在含有NOx和NH 3的最佳温度范围内的温度下,贫空燃比废气被供给到NH 3分解催化剂中,排气中的NOx以及NH 3是 完全由NH3分解催化剂分解。
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