Summary: | 碩士 === 嘉南藥理科技大學 === 環境工程與科學系碩士班 === 95 === This study is to assess the generation or depletion on air pollutants including CO, HCs and polycyclic aromatic hydrocarbons (PAHs) emission from gasoline-powered engines fueled commercial 95-leadfree gasoline (95-LFG), 95-leadfree base gasoline (95-LFBG) and 95-LFBG blended with 3% alcohol (95-E3), respectively. More Than 12 test vehicles were operated and simulated by USEPA Federal Test Procedure (FTP-75) modes with standard cold-start, hot-soak, and highway fuel economy test driving schedule. EPA has decided to modify the gasoline specification; therefore, 3% alcohol will be added in gasoline to reduce the air pollutants as previous assessment in Taiwan. However, adding ethanol in gasoline was the tide for the sake of environmental reason. The pollutant emitted from gasoline-powered engines in Taiwan is a serious issue.
More than different 10 automobiles were tested and gaseous and particle-bound PAH samples were collected after traditional pollutant sampler. A gas chromatograph/mass spectrometer (GC/MS) was employed to analyze 21 individual PAHs emitted from the exhaust of engines. The total PAHs and their BaPeq emission characteristics was also estimated and calculated by BaP toxic equivalent factor (TEF).
In this study, emitted by 95-LFBG powered engine had highest total PAHs concentration for 1260 �慊/Nm3. The other gasoline-powered engines had 7640 �慊/Nm3 (95-E3), 786 �慊/Nm3 (95-LFG) under FTP-75 operation condition. For the PAH emission factor in fuel consumption unit, the sequence was 95-LFBG (239 mg/L-fuel), 95-E3 (206 mg/L-fuel) and 95-LFG (167 mg/L-fuel). Under the different EPA phase regulation on the emission of automobile, the total PAH emitted from Phase II vehicles were 1120 �慊/Nm3 (95-LFG) and 1450 �慊/Nm3 (95-E3). In the same time, the total PAH emitted from Phase III vehicles were 646 �慊/Nm3 (95-LFG) and 680 �慊/Nm3 (95-E3).
From the results of this study, gasoline with 3% ethanol may reduce CO and HCs due to its oxygen content, however, there is no significant effect on the depletion of PAH emission. Furthermore, adding more alcohol in gasoline should be assessed under this operation condition.
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