Emissions of Polycyclic Aromatic Hydrocarbons and Particle-Bound Metals from a Diesel Engine Generator Fueled with Waste Cooking Oil-Based Biodiesel Blends

Abstract

This study investigates the emission of a heavy-duty diesel engine generator fueled with waste cooking oil (WCO)-based biodiesel blends (W) and operated at 1.5 and 3.0 kW loads. A brand of pure fossil diesel was adopted as the base fuel, with 20% and 40% WCO-based biodiesel added into the based fuel to form W20 and W40 blends, respectively. The emission characteristics of PM, metals and PAHs were analyzed. Experimental results indicate that alternative WCO-based fuels had slightly higher fuel consumption rates (FCR) and brake specific fuel consumptions (BSFC) than conventional diesel (0.6-4.1% for FCR and 1.0-7.6% for BSFC), and similar engine thermal efficiency. The PM emissions reductions when using W20 and W40 were 19% and 6.5%, respectively, at 1.5 kW, and 27% and 19%, respectively, at 3.0 kW. The emissions of particle-bound metals were 13.6-13.8% lower when using W20 than using conventional diesel, but 12.0-12.3% higher when using W40. The metal contents of PM rose with the addition of WCO-based biodiesel. The metal elements of PM were dominated (> 90% mass) by Na, Mg, Al, K, Ca, Fe and Zn, while the major trace metals were Mn, Cu, Sr and Pb. The use of WCO-based biodiesel blends reduced the emissions of total-PAHs (44.0% in average) and totalBaP eq (80.2% in average). The mass reductions of MMW-and HMW-PAHs using W20 and W40 were more significant at 3.0 kW than at 1.5 kW, while the reduction of LMW-PAHs was greater at 1.5 kW than at 3.0 kW. Thus, the reduction in total-BaP eq was greater at the higher engine load. Accordingly, we conclude that the WCO-based biodiesel is a potential candidate of cleaner alternative energy sources.

Chemical Composition of Diesel/Biodiesel Particulate Exhaust by FTIR Spectroscopy and Mass Spectrometry: Impact of Fuel and Driving Cycle

“…An advantage of using biofuel is that it reduces PM mass, particle number, and size as compared to diesel fuel (Betha and Balasubramanian, 2011;Chang et al, 2014). Reduction of polycyclic aromatic hydrocarbons (PAHs) (Lin et al, 2017) and elemental carbon (EC) (Na et al, 2015) emissions were concomitantly observed. Many campaigns have been conducted over the past decade regarding the characterization of air quality degradation resulting from biodiesel/biofuel and diesel-fueled engine emissions (Dwivedi et al, 2006;Betha and Balasubramanian, 2011).…”

Emissions of PM2.5-bound Polycyclic Aromatic Hydrocarbons and Metals from a Diesel Generator Fueled with Biodiesel Converted from Used Cooking Oil

“…Because PAHs are semi-volatile, they may condense on surfaces within the engine, and then damage the engine through 'wetstacking' (Überall et al, 2015). Using biodiesel, or increasing the oxygen content of the fuel, leads to more complete combustion, and helps to inhibit PAH formation (Lin et al, 2017). Thus, the effect of biodiesel blends on the formation of PAHs in exhausts is important to understand from the perspectives of human health, the environment and its influence on engine failure.…”

“…Biodiesel is recognized to be one of the ways to successfully reduce diesel engine pollutant emissions (Wang et al, 2016;Lin et al, 2017;Redfern et al, 2017). Biodiesel is environmentally friendly, but has slightly higher fuel consumption (Mwangi et al, 2015;Lin et al, 2017) and levels of trace metals on the particles in the exhausts than standard diesel fuel under the same operating conditions (Shukla et al, 2017).…”

“…Biodiesel is recognized to be one of the ways to successfully reduce diesel engine pollutant emissions (Wang et al, 2016;Lin et al, 2017;Redfern et al, 2017). Biodiesel is environmentally friendly, but has slightly higher fuel consumption (Mwangi et al, 2015;Lin et al, 2017) and levels of trace metals on the particles in the exhausts than standard diesel fuel under the same operating conditions (Shukla et al, 2017). Moreover, some characteristics of biodiesel, such as density, viscosity, and cold flow properties make it unsuitable for direct use in high addition percentages (over 50 vol%) as an alternative fuel (How et al, 2012;Yilmaz and Davis, 2016).…”

Persistent Organic Pollutant Reductions from a Diesel Engine Generator Fueled with Waste Cooking Oil-based Biodiesel Blended with Butanol and Acetone

“…Diesel engine exhausts (DEEs) may cause adverse health effects due to their varied chemical compositions, which include carbonaceous matter (Cheng et al, 2015), trace metals (Lin et al, 2005;Lin et al, 2008), polycyclic aromatic hydrocarbons (PAHs) (Lin et al, 2012;Lin et al, 2017) and even persistent organic pollutants (POPs) (Gullett and Ryan, 2002;Chang et al, 2014a;Chen et al, 2017). In urban areas, the emissions emitted from diesel engines contain pollutants harmful to human health, such as carcinogens * Corresponding author.…”