US 12,435,655 B2
Active hydrocarbon trap for reduction of emissions from internal combustion engines using a three-valve configuration
Alexander Voice, Detroit, MI (US); Kaustav Bhadra, Ann Arbor, MI (US); Esam Hamad, Brighton, MI (US); and Praveen Kumar, New Hudson, MI (US)
Assigned to SAUDI ARABIAN OIL COMPANY, Dhahran (SA)
Filed by ARAMCO SERVICES COMPANY, Houston, TX (US)
Filed on Dec. 20, 2023, as Appl. No. 18/390,770.
Prior Publication US 2025/0207523 A1, Jun. 26, 2025
Int. Cl. F01N 3/28 (2006.01); F01N 3/08 (2006.01); F01N 13/00 (2010.01)
CPC F01N 3/2882 (2013.01) [F01N 3/0814 (2013.01); F01N 13/009 (2014.06); F01N 13/011 (2014.06)] 8 Claims
OG exemplary drawing
 
1. A device for reducing emissions from an internal combustion engine having a close-coupled catalyst, the device comprising:
an underbody catalyst disposed downstream of the close-coupled catalyst;
a hydrocarbon trap disposed downstream of the underbody catalyst; and
a three-valve system configured to dynamically adjust a flow path of exhaust from the internal combustion engine through the underbody catalyst or the underbody catalyst and the hydrocarbon trap, to reduce emissions, comprising:
a first flow line from the close-coupled catalyst to the underbody catalyst;
a second flow line from the underbody catalyst to an ambient environment with a first valve disposed in the second flow line;
a third flow line from the underbody catalyst to the hydrocarbon trap with a second valve disposed in the third flow line;
a fourth flow line from the hydrocarbon trap to the ambient environment with a third valve disposed in the fourth flow line;
a fifth flow line from the hydrocarbon trap to the internal combustion engine; and
a control system, configured to:
open the second valve and the third valve and close the first valve during a period of time corresponding to a cold engine condition having a temperature less than 125° C.;
open the first valve and the second valve and close the third valve during a period of time corresponding to a warm engine condition having a temperature in a range of 125 to 300° C.;
open the first valve, close the second valve, and close the third valve during a period of time corresponding to a hot engine condition having a temperature in a range above 350° C.