US 11,946,428 B2
Systems and methods for reducing aftertreatment system NOx emissions
Matthew K. Volmerding, Columbus, IN (US); and Simon Guest, Columbus, IN (US)
Assigned to Cummins Emission Solutions Inc., Columbus, IN (US)
Filed by Cummins Emission Solutions Inc., Columbus, IN (US)
Filed on Jun. 28, 2022, as Appl. No. 17/851,832.
Claims priority of provisional application 63/216,105, filed on Jun. 29, 2021.
Prior Publication US 2022/0412278 A1, Dec. 29, 2022
Int. Cl. F02D 41/02 (2006.01); F01N 3/021 (2006.01); F01N 3/20 (2006.01); F01N 3/32 (2006.01); F02B 37/04 (2006.01); F02B 37/12 (2006.01); F02D 41/04 (2006.01); F02D 41/06 (2006.01)
CPC F02D 41/024 (2013.01) [F01N 3/021 (2013.01); F01N 3/2013 (2013.01); F01N 3/2033 (2013.01); F01N 3/208 (2013.01); F01N 3/32 (2013.01); F02B 37/12 (2013.01); F02D 41/042 (2013.01); F02D 41/062 (2013.01); F01N 2610/02 (2013.01); F01N 2610/10 (2013.01); F01N 2610/1406 (2013.01); F01N 2900/1402 (2013.01); F01N 2900/16 (2013.01); F02B 37/04 (2013.01); F02D 2200/0802 (2013.01); F02D 2200/70 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A controller for an aftertreatment system coupled to an engine, the controller configured to:
in response to receiving an engine shutdown signal, determine an estimated amount of ammonia stored on a selective catalytic reduction (SCR) catalyst included in the aftertreatment system;
in response to determining that the estimated amount of ammonia stored in the SCR catalyst is less than an ammonia storage threshold, activate (i) an electric turbo or an air pump, and (ii) a heater, such that the electric turbo or the air pump causes a flow of gas through the heater and thereby causes a flow of a heated gas towards the SCR catalyst;
cause insertion of a reductant into an exhaust gas flowing through the aftertreatment system; and
in response to determining that the estimated amount of ammonia stored in the SCR catalyst is equal to or greater than the ammonia storage threshold, cause shutdown of the engine.