Biodiesel emissions

Table 10.2 Average biodiesel emissions (%) compared with conventional diesel.

National Biodiesel Board, in Biodiesel Emissions , Jefferson City, MO, 2004. 

Schumacher, L. G., W. Marshall, J. Krahl, and W. B. Wet. 2001. Biodiesel Emissions Data from Series 60 DDC Engines. Transactions of the ASAE 44 (6) 1465-146S. 

TABLE 3.6 Average Biodiesel Emissions (%) Compared to Conventional Diesel ... 

Combustion and emission characteristic tests on soybean oil biodiesel have been performed to assess the health effects associated with soybean-based biodiesel emissions. A program at the US Environmental Protection Agency (EPA) showed recently that particulate mass (PM) emissions were 30% lower with BlOO combustion, compared to BO (pure petroleum-derived diesel). Moreover, the latest results were also richer in CO, while being slightly lower in NO and organic acids than BlOO (Mutlu et al., 2015). 

Rounce, P., Tsolakis, A., Leung, P., York, A.P.E., 2010. A comparison of diesel and biodiesel emissions using dimethyl carbonate as an oxygenated additive. Energy Fuels 24, 4812-4819. 

In addition to greenhouse benefits, biodiesels offer environmental advantages over conventional diesel. Biodiesels produce similar NO, emissions to conventional diesel, fuel but less particulate matter. Biodiesel is more biodegradable that conventional diesel making any spills less damaging in sensitive areas. In general biodiesel provides more lubrication to the fuel system than low-sulfur diesel. 

Due to its particular composition, biodiesel is biodegradable and allows reduced emissions, in terms of particulates and polycyclic aromatic hydrocarbons. Instead, the results of the combustion of biodiesel are contentious in relation to so-called NOx emissions, where it has been observed that such emissions are more or less increased, with respect to conventional diesel, depending on the characteristics of the engine in which it is used ... 

C. Sharp, Exhaust emission and performance of diesel engines with biodiesel fuels, Southwest Research Institute, 1998. 

Table 9.3 Energy values, costs and emissions per hectare in the comparison of the production of biodiesel by oilseed rape and bioethanol by wheat crops. (Adapted from [4]).

On the other hand, biodiesel is a good additive to diesel fuel, reducing smoke, particulate matter (PM) and CO emissions. Engines using E-diesel with 10%... 

The commercial biodiesel fuel significantly reduced PM exhaust emissions (75-83%) compared to the petrodiesel base fuel. However, NO exhaust emissions increased slightly with commercial biodiesel compared to the base fuel. The chain length of the compounds had little effect on NO, and PM exhaust emissions, while the influence was greater on HC and CO, the latter being reduced with decreasing chain length. Non-saturation in the fatly compounds causes an increase in NO exhaust emissions. 

Many studies on the performances and emissions of compression ignition engines, fueled with pme biodiesel and blends with diesel fuel, have been conducted and are reported in the literature (Laforgia and Ardito, 1994). Fuel characterization data show some similarities and differences between biodiesel and petrodiesel fuels. The sulfur content of petrodiesel is 20 to 50 times that of biodiesel. Biodiesel has demonstrated a number of promising characteristics, including reduction of exhaust emissions. 

For soybean-based biodiesel at this concentration, the estimated emission impacts for percent change in emissions of NO,, particular matter (PM), HC, and CO were +20%, -10.1%, -21.1%, and -11.0%, respectively (EPA, 2002). The use of blends of biodiesel and diesel oil are preferred in engines in order to avoid some problems related to the decrease of power and torque, and to the increase of NO, emissions (a contributing factor in the localized formation of smog and ozone) that occurs with an increase in the content of pure biodiesel in a blend. Emissions of all pollutants except NO appear to decrease when biodiesel is used. The use of biodiesel in a conventional diesel engine dramatically reduces the emissions of unbumed hydrocarbons, carbon dioxide, carbon monoxide, sulfates, polycyclic aromatic hydrocarbons, nitrated polycyclic aromatic hydrocarbons, ozone-forming hydrocarbons, and particulate matter. The net contribution of carbon dioxide from biomass combustion is small. 

Canakei, M., Erdil, A., Areaklioglu, E. 2006. Performanee and exhaust emissions of a biodiesel engine. Appl Energy 83 594-605. 

EPA(US Environmental Proteetion Agency). 2002. A comprehensive analysis of biodiesel impaets on exhaust emissions. Draft Technical Report, EPA420-P-02-001, October 2002. EPA, Washington, DC. 

Laforgia, D., Ardito, V. 1994. Biodiesel fueled IDl engines performanees, emissions and heat release investigation. Biores Teehnol 51 53-59. 

Environmental concerns have been raised in recent years dealing with greenhouse gases produced from the transportation industry. A contributing cause of these emissions is the combustion of fossil fuels such as diesel, gasoline and oil. A strong enviromnental initiative has pushed for the development of alternative fuels such as ethanol and biodiesel in pure and blended forms (Demirbas, 2008). 

A conceptual design and selection of an ATR biodiesel processor for a vehicle fuel cell auxiliary power unit were reported by Specchia et al. [81]. Three processor options were compared for H2 production with respect to efficiency, complexity, compactness, safety, controllability and emissions. The ATR with both high-temperature shift (HTS) and low-temperature shift (LTS) reactors showed the most promising results. 

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