Process for operating an exhaust gas purification apparatus comprising a sulfur-trap and a nitrogen oxide storage catalytic converter
摘要
An internal combustion engine (2) exhaust gas purification device (1) is operated predominantly using lean air-fuel ratios. It has a sulfur filter (5) followed by a NOx storage catalyzer (6). Process for operating an internal combustion engine exhaust gas purification device comprises:- (a) storing the nitrogen oxides in the exhaust gas on a storage catalyst and the sulfur oxides on the sulfur trap at air factors of above 1 and exhaust gas temperatures TK within the activity window DELTA TNOX, in which the exhaust gas temperature TS is smaller than the desulfurization temperature TS DeSOx, and cyclically reducing the air factor of the exhaust gas below 1 to release the stored nitrogen oxides; and (b) desulfurizing the sulfur trap by increasing the exhaust gas temperature TS above the desulfurization temperature of the sulfur trap and reducing the air factor of the exhaust gas below 1 and cyclically repeating steps (a) and (b).
申请公布号
EP0945608(A3)
申请公布日期
2000.06.21
申请号
EP19990105640
申请日期
1999.03.19
申请人
DEGUSSA-HUELS AKTIENGESELLSCHAFT
发明人
STREHLAU, WOLFGANG, DR.;GOEBEL, ULRICH, DR.;LOX, EGBERT, DR.;MUELLER, WILFRIED;DOMESLE, RAINER, DR.