Effect of POMDME Blend on PAH Emissions and Particulate Size Distribution from an In-Use Light-Duty Diesel Engine

Abstract

<div class="section abstract"><div class="htmlview paragraph">Polyoxymethylene dimethyl ether (POMDME) is a synthetic fuel from alternative energy sources, which can be blended in any ratio with petroleum diesel fuel.</div><div class="htmlview paragraph">The regulated and non-regulated emissions, especially polyaromatic hydrocarbons (PAH) and particle number size distribution (PNSD), from an old Euro-3 diesel engine fueled with a 7,5% blend of POMDME in commercial diesel fuel were measured and compared to the base diesel fuel, after adjusting exhaust gas ratio (EGR) in order to match the level of NOx emission.</div><div class="htmlview paragraph">The experimental results show a significant reduction in soot and particulate matter (PM) emissions. The number of particles smaller than 30 nm is slightly increased at low speed and low load operating conditions, while at high speed the number concentration of particles larger than 30 nm is reduced.</div><div class="htmlview paragraph">The PAH emissions were found higher for the oxygenated fuel blend than for the base fuel. This result is consistent with the exhaust gas temperature profiles during the PAH sampling which suggest that the oxidation catalyst might have a slightly lower catalytic activity when using this oxygenated fuel.</div></div>