A Novel Approach for Diesel NOX/PM Reduction Southwest Research Institute

Format:

Conference/Event

Author/Creator:

Simescu, Simescu, author.

Contributor:

Khair, Magdi

Neely, Gary

Ulmet, Vlad

Conference Name:

SAE 2010 World Congress & Exhibition (2010-04-13 : Detroit, Michigan, United States)

Language:

English

Physical Description:

1 online resource

Place of Publication:

Warrendale, PA SAE International 2010

Summary:

The US EPA emission standards for 2010 on-highway and 2014non-road diesel engines are extremely stringent, both in terms ofoxides of nitrogen (NOX) and particulate matter (PM). Dieselengines typically operate lean and use at least 40-50 percent moreair than what is needed for stoichiometric combustion of the fuel.As a result, significant excess oxygen (O₂) is present in dieselexhaust gas which prevents the application of the mature three-waycatalyst (TWC) technology for NOX control used in gasolineengines.The objective of this work was to investigate whether or not thecatalyzed DPF had a TWC-type of effect on NOX emissions and ifso, why and to what extent when used on a diesel engine operatingat reduced A/F ratio conditions. The approach was a two-step testplan: first to reduce the operating A/F ratio of the engine, closeto stoichiometric, with an acceptable engine-out smoke increase;second, to investigate the possibility of using the catalyzed DPF(cDPF) as a PM/NOX control device at low A/F ratio operation.Low A/F ratio operation, close to stoichiometric, was achievedand tuned for low soot emissions, as indicated by the AVL filtersmoke number (FSN) at five steady-state operating conditions(modes), without the aftertreatment system installed. Twoaftertreatment system configurations were tested: diesel oxidationcatalyst (DOC) and catalyzed DPF (DOC + cDPF) and cDPF alone. Bothaftertreatment system configurations were found to have a TWCeffect when the excess exhaust O₂ was reduced sufficiently and wascompletely consumed by the DOC and/or cDPF. This effect wasobserved at all five modes. The measured NOX concentrationreduction ranged from 88 to 99%. The tailpipe brake specific NOXemissions were well below 0.20 g/hp-hr at the five steady-stateoperating conditions

Notes:

Vendor supplied data

Publisher Number:

2010-01-0308

Access Restriction:

Restricted for use by site license