Exhaust gas purification system for low emission vehicle
    41.
    发明授权
    Exhaust gas purification system for low emission vehicle 失效
    低排放车辆废气净化系统

    公开(公告)号:US06167696A

    公开(公告)日:2001-01-02

    申请号:US09325655

    申请日:1999-06-04

    IPC分类号: F01N300

    摘要: An exhaust gas purification system for a lean burn internal combustion engine including a three-way catalyst, a hydrocarbon trap downstream of the three-way catalyst, a NOx trap downstream of the hydrocarbon trap, and an electrically heated catalyst located between the hydrocarbon trap and NOx trap. In one embodiment, the NOx trap includes an integral particulate filter having alternating blocked channels extending longitudinally. The inlet channels filter particulate matter and the outlet channels have a NOx absorbent wash coat for absorbing exhaust gas NOx. A method of controlling the exhaust system during cold start engine operation is provided to reduce cold start emissions. The method further includes a control procedure for activating the electrically heated catalyst for desulfation and particulate matter burn-off.

    摘要翻译: 一种用于稀燃内燃机的废气净化系统,包括三元催化剂,三元催化剂下游的烃阱,烃阱下游的NOx捕集器,以及位于烃阱和 NOx捕集器 在一个实施例中,NOx捕集器包括具有纵向延伸的交替阻塞通道的整体微粒过滤器。 入口通道过滤颗粒物质,出口通道具有吸收废气NOx的NOx吸收剂洗涤涂层。 提供冷启动发动机运转时控制排气系统的方法,以减少冷启动排放。 该方法还包括用于激活用于脱硫和颗粒物质燃烧的电加热催化剂的控制程序。

    Method for purifying exhaust gas of an internal combustion engine
    44.
    发明授权
    Method for purifying exhaust gas of an internal combustion engine 失效
    一种内燃机排气净化方法

    公开(公告)号:US5850735A

    公开(公告)日:1998-12-22

    申请号:US711597

    申请日:1996-09-10

    摘要: According to the present invention, SO.sub.X in the exhaust gas of an internal combustion engine is absorbed by a sulfate absorbent which absorbs SO.sub.X in the exhaust gas when the temperature is lower than a releasing temperature and releases the absorbed SO.sub.X when the temperature becomes higher than the releasing temperature. When the exhaust gas temperature increases during the operation of the engine and reaches the releasing temperature, the temperature of the exhaust gas flowing into the sulfate absorbent is further raised to a predetermined temperature by supplying fuel to the exhaust gas passage upstream of the sulfate absorbent. The ratio of SO.sub.3 in the SO.sub.X mixture released from the sulfate absorbent changes in accordance with the temperature, and takes the highest value at a certain temperature (i.e., a peak temperature). Therefore, when the exhaust gas temperature is raised above the peak temperature, the ratio of SO.sub.3 in the SO.sub.X mixture released from the sulfate absorbent decreases as the temperature increases. In the present invention, the above-noted predetermined temperature is selected in such a manner that the ratio of SO.sub.3 at this predetermined temperature becomes lower than the ratio of SO.sub.3 at the releasing temperature. Therefore, when SO.sub.X is released from the sulfate absorbent, the amount of SO.sub.3, i.e., the amount of particulate matter released into the atmosphere can be maintained at a low level.

    摘要翻译: 根据本发明,内燃机废气中的SO x被吸收在温度低于脱模温度时吸收废气中的SO x的硫酸盐吸收剂,并且当温度变得高于 释放温度。 当发动机运转时排气温度升高并达到释放温度时,通过向硫酸吸收剂上游的排气通道供给燃料,进一步将流入硫酸盐吸收剂的废气升温至规定温度。 从硫酸盐吸收剂释放的SO x混合物中的SO 3的比例根据温度而变化,并且在一定温度(即峰值温度)下获得最高值。 因此,当废气温度升高到高于峰值温度时,从硫酸盐吸收剂释放的SO x混合物中的SO 3比随温度升高而降低。 在本发明中,以这样的方式选择上述预定温度,使得在该预定温度下的SO 3的比例低于在释放温度下的SO 3的比例。 因此,当SOX从硫酸盐吸收剂中释放出来时,SO 3的量,即释放到大气中的颗粒物质的量可以保持在较低水平。