Transient Performance of an HC LNC Aftertreatment System Applying Ethanol as the Reductant 2012-01-1957
As emissions regulations around the world become more stringent, emerging markets are seeking alternative strategies that align with local infrastructures and conditions. A Lean NOx Catalyst (LNC) is developed that achieves up to 60% NOx reduction with ULSD as its reductant and ≻95% with ethanol-based fuel reductants. Opportunities exist in countries that already have an ethanol-based fuel infrastructure, such as Brazil, improving emissions reduction penetration rates without costs and complexities of establishing urea infrastructures. The LNC performance competes with urea SCR NOx reduction, catalyst volume, reductant consumption, and cost, plus it is proven to be durable, passing stationary test cycles and adequately recovering from sulfur poisoning. Controls are developed and applied on a 7.2L engine, an inline 6-cylinder non-EGR turbo diesel. A working system is demonstrated that passes Euro V European Stationary Cycle (ESC) and Transient Cycle (ETC), and its control strategy is described, including necessary application calibration demands. Additionally, the catalysts are upsized for a 13L FPT Industrial EU5 application, and ESC and ETC performance is compared with its production-intent urea SCR system. With comparable catalyst volumes and reductant dosing rates, emissions reduction performance is similar, both successfully meeting EU5 requirements, even with equally sufficient room to accommodate aging effects. Results and opportunities to further enhance HC LNC system performance are provided.