US 12,168,951 B2
Systems and methods for selective catalytic reduction and/or ammonia slip catalyst sulfur protection
Di Wang, Columbus, IN (US); Richard J. Ancimer, Toronto (CA); Michael J. Cunningham, Columbus, IN (US); Aleksey Yezerets, Columbus, IN (US); Jinyong Luo, Columbus, IN (US); Yadan Tang, Columbus, IN (US); and Yuhui Zha, Columbus, IN (US)
Assigned to Cummins Inc., Columbus, IN (US)
Filed by Cummins Inc., Columbus, IN (US)
Filed on Apr. 20, 2021, as Appl. No. 17/235,684.
Claims priority of provisional application 63/013,292, filed on Apr. 21, 2020.
Prior Publication US 2021/0324775 A1, Oct. 21, 2021
Int. Cl. F01N 3/20 (2006.01); B01J 23/72 (2006.01); B01J 37/08 (2006.01); F01N 3/08 (2006.01)
CPC F01N 3/208 (2013.01) [B01J 23/72 (2013.01); B01J 37/08 (2013.01); F01N 3/0885 (2013.01); F01N 2510/063 (2013.01); F01N 2570/14 (2013.01); F01N 2570/18 (2013.01); F01N 2610/03 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A method, comprising:
predicting a sulfur exposure of one or more copper-zeolite catalysts deployed in an exhaust aftertreatment system;
comparing the predicted sulfur exposure to a predefined sulfur exposure threshold, the predefined sulfur exposure threshold being an amount of sulfur present in the exhaust gas for a first predefined time period, wherein the predefined sulfur exposure threshold is greater than 1 gram of sulfur per liter of exhaust gas (gS/L);
receiving a fault code indicating that a NOx amount in exhaust gas leaving the exhaust aftertreatment system is above a predefined high NOx amount threshold;
in response to the comparison indicating that the predicted sulfur exposure of the one or more copper-zeolite catalysts is at or above the predefined sulfur exposure threshold and receiving the fault code, heating the one or more copper-zeolite catalysts to a predefined heat treatment temperature to desulfate the one or more copper-zeolite catalysts;
starting a timer in response to a temperature of the heated one or more copper-zeolite catalysts increasing by a predefined amount; and
stopping the heating of the one or more copper-zeolite catalysts based on the timer indicating that a second predefined time period has elapsed, wherein the second predefined time period is based on the predefined heat treatment temperature.