Methods and systems for an engine emission control system
AssigneeFord Global Technologies, LLC
InventorsChristine Kay Lambert, Douglas Allen Dobson
Life of this patent
Estimating the term…
Abstract
Systems and methods are provided for a layered emission control device coupled to an exhaust manifold. Various formulations may be incorporated in a plurality of layers of the device to enable various emission control functions to be grouped within spatial constraints. For example, a first layer may include a first, oxidizing catalyst, a second layer may include a HC trap, and a third layer may include a second, different oxidizing catalyst, the second layer positioned between the first and third layers. The layers may be organized to reduce functional interference and improve functional synergy between the various emission control functions.
Claims20
A layered emission control system coupled to a vehicle engine exhaust manifold, comprising:
- a first, upper layer including a first, oxidizing catalyst;
- a second, intermediate layer including a HC trap for trapping exhaust HCs;
- and
- a third, lower layer including a second, different oxidizing catalyst, wherein the second layer is positioned between the first and third layers.
A layered diesel oxidation catalyst (DOC) system, comprising:
- a first DOC layer configured to trap exhaust hydrocarbons and/or oxidize exhaust hydrocarbons to raise an exhaust temperature;
- a second DOC layer configured to trap exhaust NOx species and/or oxidize exhaust NO;
- and
- an intermediate layer, positioned between the first and second DOC layers, including a HC trap for trapping exhaust HCs.
A method of operating an emission control device coupled to an engine exhaust manifold, comprising:
- passing exhaust gas over a substrate of the device and through a plurality of catalytic layers supported by the substrate;
- oxidizing exhaust hydrocarbons in a first, top catalytic layer of the device;
- retaining exhaust hydrocarbons in a second, intermediate catalytic layer of the device;
- and
- oxidizing exhaust NO species in a third, bottom catalytic layer of the device.
Dependencies are inferred from the claim text.