Exhaust emissions and health effects of particulate matter from agricultural tractors operating on rapeseed oil methyl ester

Abstract

Exhaust emissions and their effects on the environment and human health, such as mutagenicity of particulate matter (PM) and ozone-forming potential, must be considered when using an alternative fuel. In the present work, a test engine and two agricultural tractors ran on rapeseed oil methyl ester (biodiesel) or conventional diesel fuel as well as blends thereof. The objective was to detect any disproportionately positive or negative effects depending on blend levels, because conventional diesel fuel and biodiesel can be blended in every ratio. Generally, emissions of regulated compounds changed linearly with the blend level. The known positive and negative effects of biodiesel varied accordingly. Overall, no optimal blend was found. Increasing biodiesel content of the fuel caused a linear increase in benzene emissions in the agricultural five-mode engine test, an effect that may be explained from previous studies on precombustion chemistry. In using the test engine, it was found that PM from biodiesel significantly reduced mutagenic potential compared with that from diesel fuel, although in this work PM masses were found to be reproducibly higher for biodiesel from rapeseed oil compared with conventional diesel fuel. Ozone precursors increased 10-30% when using biodiesel compared with conventional diesel fuel. Emissions of aldehydes and alkenes are mainly responsible for this effect. N 2 O emissions increased when using a catalytic converter.Paper no. J9848 in JAOCS 79, 717-724 (July 2002).

Sensitivity of Diesel Particulate Material Emissions and Composition to Blends of Petroleum Diesel and Biodiesel Fuel

“…In regards to OC aerosol emissions, there was little variation for B25, B50, and B75 blends, however, using pure biodiesel fuel (B100) resulted in increases in overall OC aerosol emission rates, mostly associated with unburned fatty acid methyl esters. Whereas prior studies have shown that PM 10 emissions decrease when blending petroleum diesel fuel with biodiesel (Schumacher et al 1996;Durbin et al 2000;Krahl et al 2002;Lapuerta et al 2003;Knothe et al 2006;Frey et al 2008), other studies showed higher emissions of particles with smaller particle diameters from diesel engines operating on biodiesel fuel blends compared with petroleum diesel fuel, associated with factors such as the fuel composition, heating value and thermodynamic properties of species in the exhaust Heikkila et al 2009). …”

The effect of triacetin as a fuel additive to waste cooking biodiesel on engine performance and exhaust emissions

“…The reason could be the toxicity of particles which increases by decreasing the particle size [38]. As a consequence the EU included PN in Euro 6 and EURO 5b emission standards for heavy-duty and light-duty vehicles.…”

Diesel engine performance and emissions with fuels derived from waste tyres

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