Reduced NOx/Hydrocarbon Emissions via Oxygen Enriched Lean Burn Engines

Lean burn spark engines are a promising technique to further reduce both NOx and hydrocarbon/carbon monoxide (HC/CO) engine emissions. Higher lean burn levels improve HC/CO oxidation while simultaneously reducing NOx formation. The NOx reduction is due to cooler flame temperatures. While the lean burn limit (beyond which combustion is poor) restricts further emission reductions, the use of oxygen enriched air (OEA) significantly extends the lean burn limit and further reduces emissions. To date, no compact supply of OEA has been available to extend the lean burn limit. Compact Membrane Systems, Inc., has developed high gas flux OEA membranes with 30 times the productivity of existing membranes. This allows compact portable OEA systems to extend automobile lean burn limits and further reduce NOx/HC/CO emissions. In Phase I, feasibility of the membranes will be demonstrated on a small (5-10 hp) engine. The goal of the project is a 40% reduction in NOx and a 15% reduction in HC emissions.