High-Efficiency NOx and PM Exhaust Emission Control for Heavy-Duty On-Highway Diesel Engines

Effects of hydrothermal aging on SiC-DPF with metal oxide ash and alkali metals

“…The regeneration temperature has to be controlled under a critical value to ensure the durability of SiC-DPF in the after-treatment system, considering the fact that large quantities of ash materials, alkali metals and H 2 O components are included in the exhaust gas. catalytic washcoat for CDPF [5,[13][14][15]17]. Therefore, when these ash materials or alkali metals join with the DPF, the SiC material of the DPF interacts with the ash materials or/and alkali metals.…”

NOx Adsorber Desulfation Techniques for Heavy-Duty On-Highway Diesel Engines

“…The results of the first and second testing phases have been previously reported. 2,3 The basis of this work revolves around the use of a dual path exhaust system incorporating CDPFs in series with NOx adsorber catalysts. NOx adsorber catalysts have been shown to achieve high NOx conversion efficiencies over wide temperature windows in lean burn applications.…”

Lean NOx Trap Catalysis for Lean Natural Gas Engine Applications

“…Furthermore, in order to reduce the amount of fuel required to regenerate the catalyst, an exhaust system with valves controlling exhaust flow was implemented to reduce the exhaust flow through the catalyst during the regeneration process. 11,12,13 The lower exhaust flow during regeneration results in a lower oxygen mass flow and thereby, lower fuel requirement. Minimizing fuel use for catalyst regeneration is important since the fuel used for catalyst regeneration provides no useful energy and thus, represents a fuel penalty for the end user.…”

“…The approach is also applicable to other lean engines such as diesel engines, natural gas turbines, and lean gasoline engines; other research activities have focused on those applications. 8,9,10,11,12,13 Some commercialization of the technology has occurred for automotive applications (both diesel and lean gasoline engine vehicles) and natural gas turbines for stationary power. The research here specifically addresses barriers to commercialization of the technology for large lean natural gas reciprocating engines for stationary power.…”