Emissions and gas/particle partitioning of PCDD/Fs from exhaust gases of vehicles and motorcycles

• Main Authors: Shiunn-Cheng Chuang, 莊訓城
• Other Authors: Shui-Jen Chen
• Format: Others
• Language: en_US
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/78436280047383579554

博士 === 國立屏東科技大學 === 環境工程與科學系所 === 98 === This study investigated engine tailpipe exhausts of sport utility vehicles (SUVs), diesel passenger vehicles (DPVs), heavy duty diesel vehicles (HDDVs) and motorcycles to elucidate the emissions and congener characteristics of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). The conclusions of this study are summarized as follows. 1. The mean PCDD/F emission factors were 0.123, 0.0802, and 1.69 ng I-TEQ/km for SUVs, DPVs and HDDVs, respectively. The HDDVs emitted more PCDD/Fs than the other tested vehicles. 2. Compared with those of previous studies, the relatively high PCDD/F emission factors of vehicles found in this study may be attributed to the operations of cold start tests. 3. The 17 congener profiles of PCDD/Fs obtained from the three fleets were very similar and the dominant congeners were OCDD, OCDF, and 1,2,3,4,6,7,8-HpCDF (1,2,3,4,6,7,8-HpCDD for HDDV). 4. The mean PCDD/F I-TEQ emission factor of motorcycles was 0.0942 ng I-TEQ/km. The 2-stroke engines had more PCDD/F emission than the 4-stroke engines, and this trend was also true for their PCDD/F emission factors. 5. The PCDD/F emission factors of motorcycles are comparable to those of vehicles, although the former equipped cylinders much smaller than the latter. 6. Particulate-phase PCDD/Fs accounted for 78.0, 90.3 and 71.1% of total PCDD/Fs for the SUVs, DPVs and HDDV, respectively. The particulate-phase PCDD/Fs contributed more PCDD/F I-TEQ emissions than the gas-phase ones in the exhaust gases. 7. Particle reduction should be more favored than gas removal in exhausts to lower PCDD/F emission from automobiles.