C HARACTERIZING THE BIODIESEL VEHICLE EMISSIONS MADE FROM VEGETABLE OIL

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1 C HARACTERIZING THE BIODIESEL VEHICLE EMISSIONS MADE FROM VEGETABLE OIL LINDA ZOU School Engineering and Technology, Deakin University, Geelong VIC 3217 STEVEN ATKINSON School Biological and Chemical sciences, Deakin University, Geelong Vic 3217 Biodiesel manufactured from canola oil was blended with diesel and used as fuel in diesel vehicles. project aims to test emissions diesel engines using 100%, 80%, 60%, 40%, 20% biodiesel and 100% petroleum diesel, and characterise matter emissions, particularly health-related polycyclic aromatic hydrocarbons, and gaseous emissions. Both gaseous and polycyclic aromatic hydrocarbons are collected separately by filter media and XAD sorbent tube. A real time dust monitor (Dustrak) was also used to monitoring continuous dust emissions during entire testing cycle. common gaseous pollutants including NOx, HC, CO and CO2 analysed via on-line data analyser. ECE(Euro 2) drive cycle was used for all emission tests. Based on results four replicate tests each blend, it was found that particle concentration has been reduced up to 33% when engine burns 100% diesel, compare to burn 100 petroleum diesel. A general trend reduction particle emission was found when percentages biodiesel in fuel increased. A correction factor 6 was applied for real time emissions 100% biodiesel, and a correction factor 3 was applied to emissions 100% petroleum diesel. discrepancy between Dustrak and gravimetric method was likely due to fact that Dustrak monitor was calibrated using a light brown coloured dust, but diesel and biodiesel emissions black. Limited reductions about 10% found at emissions NOx, HC and CO when burning biodiesel. In case CO2, emissions biodiesel and diesel at similar levels. 18 EPA priority have been targeted, only 6 species detected in gaseous phase from samples. A 50% reduction total gaseous observed when using 100% biodiesel rar than diesel. overall levels in form much lower than gaseous. 9 individual detected in phase. Only a marginal reduction 10% was found when burning biodiesel, instead diesel. individual PAH levels in all did not display a clear trend reduction. information obtained is useful to understand emissions and its environmental impacts biodiesel made from vegetable oil. 1 Introduction Motor vehicles, especially diesel engines are major source air pollution. exhaust gases from diesel engine vehicle contain many types gaseous and air pollutants. Some emitted matter such as polycyclic aromatic hydrocarbons () have adverse effects on human health. Interest in development more environmental friendly fuels has grown steadily in recent years, biodiesel derived from vegetable oil has considered as one potential option for fuel. Biodiesel is a mono-alkyl ester-based oxygenated fuel made from vegetable oil or animal fats. It has properties similar to petroleum based diesel fuel and can be blended into conventional diesel fuel. Previous studies showed that biodiesel vegetable oil reduced emissions hydrocarbon, nitrogen oxides, matter and smoke density [1,4,5] So far most emission testing on biodiesel application are limited to analyse common gaseous pollutants, and more research is needed to know emission characteristics specific health-related. In this study, biodiesel manufactured from canola oil by an Australian supplier has not yet been tested on its emissions. This project aims to test emission diesel engines on biodiesel with commercial diesel from 100% biodiesel to 100% diesel, and characterise matter emissions, particularly health-related polycyclic aromatic hydrocarbons. 432

2 initial outcome research in biodiesel will lead to attract more attention on its effects and commit more resources to evaluating new technology. 2 Methods following procedure emission test was carried out. An adaptor has been made to connect sampling system with diesel vehicle exhaust. air-fuel-ratio specific engine has been determined. A new Toyota Helix Utility vehicle was used for gaseous and emission analysis. It has a 3-litre diesel engine and equipped with an oxidation catalytic converter. Due to very low levels collected on filters during testing cycle when using new vehicle, it was hard to achieve quantification emission. So that second vehicle was used which was 1979 model Volkswagen golf with a 1.6-litre engine. Emission tests standard testing cycle on diesel engine have been carried out using different biodiesel/diesel. ECE (Euro 2) drive cycle was used for all emission tests. It is current drive test cycle adopted by Australia. 100% biodiesel was used first for emission sampling to provide reference emission levels. n biodiesel tested at 80%, 60%, 40% 20% biodiesel, and finally 100 percent commercial petroleum diesel. Four replicate tests conducted for each blend, so as to generate statistically significant data set. Smoke laden filter papers removed from sampling holder, and conditioned in desiccator, and weighed to obtain net mass. mass gained after sampling n converted into matter/smoke concentration (mg/m3). Both smoke laden filters and XAD sorbent tubes analysed by Gas Chromatograph-Mass Spectrometer (GC- MS) to determine levels toxic air pollutants-polycyclic aromatic hydrocarbons (). data files NOx, HC, CO and CO2 downloaded and analysed to generate results. 3. Results and discussion 3.1 Particle/smoke emissions from biodiesel/diesel Based on results four replicate tests for each blend, average particle concentrations calculated toger with standard deviation and are shown in Table 1. particle concentrations have been reduced up to 33% when engine burns 100% biodiesel, compare to burn 100% petroleum diesel. Table 1 Average particle/smoke emissions from biodiesel/diesel Dustrak monitor provides information on real time emissions during entire testing cycles. Again 4 replicate tests conducted for each biodiesel/diesel. results real time emissions 100% biodiesel versus 100% diesel plotted and displayed in Figure 1, where a correction factor 6 was applied for 433

3 emissions 100% biodiesel, and a correction factor 3 was applied for emissions 100% petroleum diesel derived from gravimetric data. discrepancy between Dustrak and weighing method was likely due to fact that Dustrak monitor was calibrated by its manufacturer using standard light brown coloured dust, but diesel and biodiesel emissions black and quite different, as a result, laser back scatter sensor tended to under measure diesel and biodiesel emissions, and magnitude under-measurement was related to characteristics particles, including colour and size etc. se factors contributed to fact that when we changed fuel from 100% biodiesel to 100% petroleum diesel, Dustrak monitor responded to particles differently. This corresponded to apparent reduction visible emissions from road vehicles using biodiesel. Figure 1 Real time smoke emissions biodiesel versus diesel 3.2 Common gaseous pollutants emissions By using on-line gas data logger, four common gaseous pollutants analysed simultaneously, including nitrogen oxides (NOx), hydrocarbon (HC), carbon monoxide (CO) and carbon dioxide (CO2). gases measured and recorded every second during entire driving test cycle. Limited reductions (about 10%) emissions have been observed for NOx, HC and CO when burning biodiesel. In case CO2, emissions biodiesel and diesel at similar levels. 3.3 Polycyclic aromatic hydrocarbon () emissions Eighteen ( EPA Priority list) targeted. In all samples only 6 species detected in gaseous phase. se included naphthalene, acenapthylene, acenaphne, fluorene, phenanthrene and anthracene. Four individual (naphthalene, acenapthylene, fluorene, and phenanthrene) showed lower levels when burning biodiesel, compared to burning diesel. trends gaseous emissions different biodiesel/diesel are shown in Figure 4. total gaseous concentrations each blend are calculated and summarised in Table 2. A 50% reduction total emissions was observed when using 100% biodiesel rar than using diesel. Table 2 Total gaseous concentrations biodiesel/diesel 434

4 Figure overall samples. Out levels phase, including benzo(b)fluoranne, concentration 10% found see comparing that targeted from emissions, 9 when using burning in all Based biodiesel calculated 100% total in Table biodiesel, reduces biodiesel only gaseous detected 3. Only diesel. in Figure 5, emission total gaseous decrease a but 3 Total Figure 5 Particulate concentrations emissions 435 biodiesel/diesel biodiesel/diesel different trend emissions, small individual no clear concentrations, very chrysene, ir reduction in a marginal to diesel. Table in benz(a)anthracene, benzo(ghi)perylene. instead displayed data than pyrene, benzo(a)pyrene, listed are above /diesel lower significantly emissions much individual and six on biodiesel Đg/m3. PAH levels from plot. can phenanthrene, fluoranne, benzo(k)fluoranne, was observed 18 range biodiesel/diesel 4 Gaseous percentage is we but

5 4. Conclusions mass concentration particles/smoke decreased up to 33% when engine burned 100% biodiesel as fuel, compared to 100% petroleum diesel. A general trend reduction particle emission was observed when percentages biodiesel in fuel increased. Although observed reduction monitored by Dustrak was an overestimate due to different optical characteristics biodiesel and petroleum diesel emissions. This warrants furr study into characterisation both biodiesel and diesel particle emissions. Based on real time monitoring gaseous pollutants emission, marginal reductions (about 10%) in emission found for NOx, HC and CO when burning 100% biodiesel, compared to burning 100% petroleum diesel. emissions levels CO2 showed no difference for both biodiesel and diesel. Six gaseous detected from samples. Four ses (naphthalene, acenapthylene, fluorene, and phenanthrene) showed significantly lower levels when burning biodiesel compared to diesel. It was found that total gaseous PAH concentrations had decreased by 50% when using 100% biodiesel comparing to using diesel. overall levels 9 detected much lower than gaseous. Only a marginal reduction (10%) total was observed when replacing diesel with biodiesel. information obtained from this study can be used to gain a better understanding beneficial environmental impacts using biodiesel. Although some research has reported a lower mutagemc potency matters from biodiesel emission [2,3], furr study on understanding genotoxicity and or health effects biodiesel emissions on human cells would be valuable to support conclusion. 5. Acknowledgement We thank Ford emission testing laboratory to allow us access ir facility, and thank Mr Chris Saliba for his contribution to project. Reference 1. All, Y.; Hanna M. A. and Lecviticus L. I. (1995) Emissions and power characteristics diesel engines on methyl soyate and diesel fuel Bioresource Technology 52 pp , Elsevier Science Limited, Great Britain. 2. Bagley, S. T.; Gratz, L. D.; Johnson, J. H. and McDonald, J. F. (1998) Effects oxidation catalytic converter and a biodiesel fuel on chemical, mutagenic and particle size characteristics emissions from a diesel engine" Environmental Science and Technology 32, ppl , American Chemical Society. 3. Bunger, J., Krahl, J., Baum, K., Schroder, O., MUller, Westphal, G., Ruhnau, P. Schulz, T. G. and Hallier, E. Cytotoxic and mutagenic effects, particle size and concentration analysis diesel engine emissions using biodiesel and patrol diesel as fuel Arch Toxicol (2000) 74: Durbin, T. D.; Cfins, J. R.; Norbeck, J. M. and Smith, M. R. (2000) Effects biodiesel, biodiesel, and a syntic diesel on emissions from light heavy-duty diesel vehicles" Environmental Science & Technology 34, pp , American Chemical Society. 5. Koo, B. C. P. and Leung, D. Y. C. (2000) Emission testing on a biodiesel produced from animal fats Proceedings 3rd Asia Pacific Conference on Sustainable Energy and Environmental Technologies pp , Hong Kong. 436