Ford Global Technolgoies, LLC

Other

Joseph Robert Theis

Gopichandra Surnilla

Justin Anthony Ura

Christian Thomas Goralski, Jr

Shane Elwart

Michael James Uhrich

Giovanni Cavataio

Christine Kay Lambert

Jeffrey Allen Doering

Thomas George Leone

James Michael Kerns

Robert Walter McCabe

Todd Anthony Rumpsa

Harendra S Gandhi

William Francis Stockhausen

Douglas Allen Dobson

Hungwen Jen

Siamak Hashemi

Robert Jay Natkin

Clifford Norman Montreuil

Xiaoguo Tang

Adam Nathan Banker

Jeffrey Scott Hepburn

Stephen B Smith

Haren S Gandhi

Jason Aaron Lupescu

John M Roth

Grant Alan Ingram

Gopichandra Sumilla

William Lewis Henderson Watkins

Jun (John) Li

Rachel Alison Snow

Andrew Gregory Getsoian

Jacqueline A Lymburner

Ronald Gene Hurley

Joseph Patterson

Juston Ura

Christian T Jnr Goralski

Methods and systems are provided for a low temperature NOx adsorber (LTNA). In one example, a method includes initiating a desulfation of an LTNA responsive to an estimated sulfur exposure exceeding a threshold, the desulfation including heating the LTNA to a first threshold temperature while maintaining an exhaust oxygen level above a threshold level throughout the entire desulfation.

Methods and systems for exhaust emission control

A method utilizes a three-way catalytic converter, having a catalyst formed from a plurality of particles each including a first metal oxide center, a second metal oxide monolayer, and a catalytically active metal to decrease concentration of hydrocarbons, carbon monoxide, and nitrogen oxides in exhaust gas during stoichiometric, rich, and lean conditions, wherein a molar ratio of metal in the monolayers to metal in the centers is between about 0.01 and 0.2.

Catalyst for automotive emissions control

Methods and systems are provided for reducing engine cold-start emissions. An exhaust system having a passive NOx adsorber (PNA) may store NOx during an engine cold-start until conditions are optimal for release of the stored NOx to a downstream SCR catalyst. Based on PNA conditions, including a NOx load and a PNA bed temperature, adjustments to EGR rate and/or injection timing may be made to achieve a catalytically favorable ratio of NOx species upstream of the SCR catalyst, after the SCR catalyst has reached its light-off temperature.

Method of controlling NOx by PNA

An exhaust system for a diesel engine is disclosed. The exhaust system may include a diesel oxidation catalyst (DOC) configured to receive exhaust gases from the engine and oxidize hydrocarbons in the exhaust gases and a passive NOx adsorber (PNA) downstream from the DOC and configured to store NOx from the exhaust gases at temperatures up to 150&#xb0; C. A selective catalytic reduction (SCR) system may be downstream from the PNA and configured to reduce NOx in the exhaust gases. The PNA may be configured to release the stored NOx at temperatures above 200&#xb0; C. The DOC upstream of the PNA may reduce the amount of NO that is generated by the PNA by oxidizing hydrocarbons before they reach the PNA.

Emissions reduction system

Methods and systems are provided for improving engine exhaust emissions while enabling exhaust catalyst regeneration following an engine lean event. Prior to a VDE event, or prior to an engine idle-stop, ammonia is produced and stored on an exhaust underbody SCR catalyst. Then, during the engine restart after the VDE mode or the idle-stop, the stored ammonia is used to treat exhaust NOx species while an upstream exhaust underbody three-way catalyst is regenerated.

NOx control during engine idle-stop operations

Embodiments are described to improve the durability of a lean NOaftertreatment system. According to one embodiment of the present invention an air injection system is used to inject air continuously into the exhaust system between the upstream three-way catalyst and the downstream selective catalytic reduction (SCR) catalyst when the engine is operating at stoichiometric or rich air/fuel ratios and the exhaust temperatures are above a calibratable level (e.g., 700&#xb0; C.). In another embodiment, an oxidation catalyst is positioned downstream of the air injection point to prevent exothermic reactions from occurring on the SCR. In another embodiment, the reductant for the SCR is generated in-situ. In yet another embodiment, a diverter valve with a reduction catalyst in a bypass arm is utilized to bypass the SCR during high load conditions.

Air-injection system to improve effectiveness of selective catalytic reduction catalyst

NOx control during cylinder deactivation

Embodiments for controlling exhaust oxygen concentration are provided. In one example, an engine method comprises operating the engine with lean combustion, and when exhaust oxygen concentration is below a threshold, injecting air into an exhaust passage between a first emission control device and an SCR device. In this way, excess emissions may be converted while operating with lean combustion.

Exhaust air injection

In one embodiment, a method for an engine comprises operating the engine with an upstream exhaust sensor, intermediate exhaust sensor, and downstream exhaust sensor each indicating rich, adjusting engine operation to operate the engine with an upstream exhaust sensor, intermediate exhaust sensor, and downstream exhaust sensor each indicating lean, adjusting engine operation to operate the engine with the upstream exhaust sensor indicating rich and the intermediate and downstream exhaust sensors each indicating lean, and indicating degradation of an SCR catalyst based on when the intermediate and downstream exhaust sensors switch from lean to rich.

SCR catalyst diagnostics

Embodiments are described to improve the durability of a lean NOaftertreatment system. According to one embodiment of the present invention an air injection system is used to inject air continuously into the exhaust system between the upstream three-way catalyst and the downstream selective catalytic reduction (SCR) catalyst when the engine is operating at stoichiometric or rich air/fuel ratios and the exhaust temperatures are above a calibratible level (e.g., 700&#xb0; C.). In another embodiment, an oxidation catalyst is positioned downstream of the air injection point to prevent exothermic reactions from occurring on the SCR. In another embodiment, the reductant for the SCR is generated in-situ. In yet another embodiment, a diverter valve with a reduction catalyst in a bypass arm is utilized to bypass the SCR during high load conditions.

Air-injection system to improve effectiveness of selective catalytic reduction catalyst for gasoline engines

According to one embodiment of the present invention a selective reduction catalyst system with a broad temperature window for lean-burn gasoline and diesel engines is disclosed. The system includes a first and second zone, wherein the first zone is composed of an iron SCR catalyst and a second zone is composed of a copper SCR catalyst, and wherein the second zone is positioned downstream of the first zone. In another embodiment, a small copper SCR catalyst is placed in front of a second zone composed of an iron SCR catalyst and a third zone composed of a copper SCR catalyst, wherein the volume of the first copper SCR catalyst is a fraction of the volume of the second copper SCR catalyst. In yet another embodiment, a diverter valve would be included in the system to eliminate any NOpenalty produced by the front Cu SCR catalyst.

Selective catalytic reduction catalyst system with expanded temperature window

According to at least one aspect of the present invention, there is provided an emission control system which includes a reductant injector injecting a pre-determined amount of a reductant into a vehicle exhaust passage, and sensors measuring an exhaust space velocity, a selective catalytic reduction (SCR) catalyst temperature, and a before-SCR nitrogen oxide (NO) concentration, wherein the predetermined amount of the reductant is a function of the exhaust space velocity, the before-SCR NOconcentration, and the SCR catalyst temperature. In at least one particular embodiment, the predetermined amount of the reductant is measured according to equation (I) y=ax; wherein y is the flow of the reductant; x is the product of the exhaust space velocity and the before-SCR NOconcentration; and 'a' and 'n' are each independently a function of the catalytic temperature (&#x201c;T&#x201d;) of the selective catalytic reduction catalyst.

Emission control system with an optimized reductant injection model

A method for remediating a NOx-containing lean diesel emission includes providing a LNT/SCR catalyst system including a SCR catalyst and a first and second LNT. The SCR catalyst is disposed downstream of the second LNT which is disposed downstream of the first LNT. The lean NOx-containing diesel emission is introduced to the first LNT with the NOx being absorbed on to the first LNT forming a substantially NOx-free lean diesel emission. An exotherm generating agent is introduced to the substantially NOx-free diesel emission between the first LNT and the second LNT to form a reactive lean diesel emission. The reactive lean diesel emission is introduced to the second LNT generating a quantity of heat effective for desorbing absorbed NOx. A reducing agent is introduced into the desorbed NOx between the second LNT and SCR catalyst. The desorbed NOx diesel emission is remediated in the SCR catalyst.

Method for remediating emissions

An emissions-control system of a vehicle is provided, having an SCR device disposed downstream of an LNT in the exhaust. During an enrichment interval to purge the LNG, a duration of an enrichment subinterval beginning after a sensor indicates rich breakthrough is adjusted in response to an aging of the LNT. In this way, it is possible to modify LNT regeneration based on catalyst performance and thereby generate sufficient ammonia for improved operation of the SCR device.

SCR emissions-control system

Growing community of inventors

Rockwood, MI, United States of America

Joseph Robert Theis