Exhaust after-treatment system having an oxidation component bypass for low temperature SCR
View Patent ↗An exhaust after-treatment system that is configured to treat an exhaust produced by an engine, and includes a bypass passage including an inlet for receiving an amount of the exhaust from an exhaust passage. A first exhaust treatment component is located within the bypass passage, and a valve is located proximate the bypass passage that is configured to control the amount of the exhaust that enters the inlet of the bypass passage. A second exhaust treatment component is located in the exhaust passage downstream from the inlet of the bypass passage, wherein an outlet of the bypass passage communicates the exhaust treated by the first exhaust treatment component back to the exhaust passage at a location that is downstream from the second exhaust treatment component such that the exhaust treated by the first exhaust treatment component does not interact with the second exhaust treatment component.
1. An exhaust after-treatment system that is configured to treat an exhaust produced by an engine, the system comprising:
an exhaust passage for carrying the exhaust produced by the engine;
a bypass passage including an inlet for receiving an amount of the exhaust from the exhaust passage;
a first exhaust treatment component located within the bypass passage;
a valve located proximate the bypass passage that is configured to control the amount of the exhaust that enters the inlet of the bypass passage; and
a second exhaust treatment component located in the exhaust passage downstream from the inlet of the bypass passage,
wherein an outlet of the bypass passage communicates the exhaust treated by the first exhaust treatment component back to the exhaust passage at a location that is downstream from the second exhaust treatment component, the exhaust treated by the first exhaust treatment component does not interact with the second exhaust treatment component wherein the outlet includes a length that is greater than a length of the second exhaust treatment component, and extends co-axially with the exhaust passage and through a center of and outward from the second exhaust treatment component.
2. The system according to claim 1 , further comprising an injector configured to dose an exhaust treatment fluid into the exhaust passage, the injector only being located at a single location that is positioned upstream of the bypass passage.
3. The system according to claim 1 , further comprising a third exhaust treatment component and a fourth exhaust treatment component in the exhaust passage and located downstream from the second exhaust treatment component.
4. The system according to claim 1 , wherein the valve is passively controlled or actively controlled.
5. The system according to claim 4 , further comprising a controller that is configured to actively control the valve.
6. An exhaust after-treatment system that is configured to treat an exhaust produced by an engine, the system comprising:
an exhaust passage for carrying the exhaust produced by the engine;
a bypass passage including an inlet for receiving an amount of the exhaust from the exhaust passage;
a first exhaust treatment component located within the bypass passage;
a valve located proximate the bypass passage that is configured to control the amount of the exhaust that enters the inlet of the bypass passage; and
a second exhaust treatment component located in the exhaust passage downstream from the inlet of the bypass passage,
wherein an outlet of the bypass communicates the exhaust treated by the first exhaust treatment component back to the exhaust passage at a location that is downstream from the second exhaust treatment component, the exhaust treated by the first exhaust treatment component does not interact with the second exhaust treatment component, the exhaust after-treatment system further comprising a canister in communication with the exhaust passage,
wherein the canister houses an entirety of the bypass passage, the first exhaust treatment component located within the bypass passage, the valve located proximate the bypass passage, and the second exhaust treatment component located downstream from the inlet of the bypass passage.
7. The system according to claim 6 , wherein the outlet includes a length that is greater than a length of the second exhaust treatment component, and extends co-axially with the exhaust passage and through a center of and outward from the second exhaust treatment component.
8. An exhaust after-treatment system that is configured to treat an exhaust produced by an engine, the system comprising:
an exhaust passage for carrying the exhaust produced by the engine;
a bypass passage including an inlet for receiving an amount of the exhaust from the exhaust passage;
a first selective catalytic reduction (SCR) component located within the bypass passage;
a valve located proximate the bypass passage that is configured to control the amount of the exhaust that enters the inlet of the bypass passage, and always permit an amount of the exhaust to pass through the valve downstream from the inlet of the bypass passage;
an injector configured to dose an exhaust treatment fluid into the exhaust passage, the injector only being located at a single location that is positioned upstream of the bypass passage;
an oxidation exhaust treatment component located in the exhaust passage downstream from the inlet of the bypass passage; and
a second SCR component located downstream from the oxidation exhaust treatment component,
wherein an outlet of the bypass passage communicates the exhaust treated by the first SCR component back to the exhaust passage at a location that is downstream from the oxidation exhaust treatment component and upstream from the second SCR component, wherein the exhaust treated by the first SCR component does not interact with the oxidation exhaust treatment component, wherein the outlet includes a length that is greater than a length of the oxidation exhaust treatment component, and extends co-axially with the exhaust passage and through a center of and outward from the oxidation exhaust treatment component.
9. The system according to claim 8 , further comprising a particulate filter located downstream from the oxidation exhaust treatment component and upstream from the second SCR component, and a slip catalyst located downstream from the second SCR component.
10. The system according to claim 8 , further comprising a controller that is configured to actively control the valve.
11. An exhaust after-treatment system that is configured to treat an exhaust produced by an engine, the system comprising:
an exhaust passage for carrying the exhaust produced by the engine;
a bypass passage including an inlet for receiving an amount of the exhaust from the exhaust passage;
a first selective catalytic reduction (SCR) component located within the bypass passage;
a valve located proximate the bypass passage that is configured to control the amount of the exhaust that enters the inlet of the bypass passage, and always permit an amount of the exhaust to pass through the valve downstream from the inlet of the bypass passage;
an injector configured to dose an exhaust treatment fluid into the exhaust passage, the injector only being located at a single location that is positioned upstream of the bypass passage;
an oxidation exhaust treatment component located in the exhaust passage downstream from the inlet of the bypass passage; and
a second SCR component located downstream from the oxidation exhaust treatment component,
wherein an outlet of the bypass passage communicates the exhaust treated by the first SCR component back to the exhaust passage at a location that is downstream from the oxidation exhaust treatment component and upstream from the second SCR component, wherein the exhaust treated by the first SCR component does not interact with the oxidation exhaust treatment component, the exhaust after-treatment system further comprising a canister in communication with the exhaust passage,
wherein the canister houses an entirety of the bypass passage, the first SCR component located within the bypass passage, the valve located proximate the bypass passage, and the oxidation exhaust treatment component located downstream from the inlet of the bypass passage.
12. The system according to claim 11 , wherein the outlet includes a length that is greater than a length of the oxidation exhaust treatment component, and extends co-axially with the exhaust passage and through a center of and outward from the oxidation exhaust treatment component.
13. An exhaust after-treatment system that is configured to treat an exhaust produced by an engine, the system comprising:
an exhaust passage for carrying the exhaust produced by the engine;
a canister in communication with the exhaust passage;
a bypass passage entirely provided in the canister, the bypass passage including an inlet for receiving an amount of the exhaust that enters the canister from the exhaust passage;
a first selective catalytic reduction (SCR) component located within the bypass passage;
a valve located in the canister proximate the bypass passage that is configured to control the amount of the exhaust that enters the inlet of the bypass passage, and always permit an amount of the exhaust to pass through the valve downstream from the inlet of the bypass passage;
an injector configured to dose an exhaust treatment fluid into the exhaust passage at a single location that is positioned upstream of the canister;
an oxidation exhaust treatment component located in the canister downstream from the inlet of the bypass passage; and
a second SCR component located in the canister downstream from the oxidation exhaust treatment component,
wherein an outlet of the bypass passage communicates the exhaust treated by the first SCR component back to a location in the canister that is downstream from the oxidation exhaust treatment component and upstream from the second SCR component, wherein the exhaust treated by the first SCR component does not interact with the oxidation exhaust treatment component.