| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide technology capable of completing SOx poisoning recovery control in a short period of time, in the SOx poisoning recovery control against an storage reduction type NOx catalyst. <P>SOLUTION: A lowering degree against time to start the SOx poisoning recovery control (SOx emission speed lowering degree Ddw) of SOx emission speed caused by reduction of SOx stored quantity of the NOx catalyst is estimated in the SOx poisoning recovery control. Thereafter, lowering of the SOx emission speed Vsox in the SOx poisoning recovery control is restrained by raising catalyst bed temperature Tc up to target temperature Tct on the high temperature side and lowering an exhaust air-fuel ratio A/F down to a target air-fuel ratio A/Ft on the rich side as the SOx emission speed lowering degree Ddw becomes larger. <P>COPYRIGHT: (C)2009,JPO&INPIT |
