NO_x reduction with natural gas for lean large-bore engine applications using lean NO_x trap aftertreatment

Large-bore natural gas engines are used for distributed energy and gas compression since natural gas fuel offers a convenient and reliable fuel source via the natural gas pipeline and distribution infrastructure. Lean NO_x trap catalysts for lean natural gas engines were presented. Testing was performed on a Cummins C8.3G (CG-280) engine on a motor dynamometer. Lean NO_x trap catalysts were tested for NO_x reduction performance under various engine operating conditions, and the utilization of natural gas as the reductant fuel source was characterized. Engine test results show that temperature greatly affects the catalytic processes involved, specifically methane oxidation and NO_x storage on the lean NO_x trap. Lean NO_x trap catalysts could achieve high (> 90%) NO_x reduction efficiencies in exhaust from lean burn natural gas engines. Natural gas could be used as the source reductant for regeneration of the lean NO_x trap. This is an abstract of a paper presented at the Gas Technology Institute's Natural Gas Technologies 2005 Conference (Orlando, FL 1/30/2005-2/2/2005).