| According to the worsening haze situation in China, PM emission should be controlled from sources. While the number of diesel vehicles considered as the main source of PM emission has increased year by year, the research on the PM emission characteristics of diesel vehicles is relatively lack. To sum up, this study used on-road test to obtain the emission factors（EFs） and characteristics of PM and its compositions of five road diesel vehicles and six non road diesel vehicles in the actual driving and operating conditions. In addition, the EFs and characteristics of PM2.5 and its components for road vehicles in Yantai city were measured by using tunnel test, and we estimated the amount of PM2.5 emissions from gasoline and diesel vehicles in Yantai city.The range of PM emission rate for five diesel trucks driving on different roads was 0.254-3.16 g hr-1. PM emission rates on different types of road ranged as highway>secondary road>main road. And the PM emission rate has a great relationship with the Bin interval distribution. The range of EFs of PM for five diesel trucks driving on different roads was the 176-951 mg kg-1 fuel. The ranges of EFs of OC and EC were 0.000-155 mg kg-1 fuel and 4.72-292 mg kg-1 fuel, respectively. And the ratio of OC/EC was higher than other research results, which may cause by instantaneous driving changes of road diesel vehicles in the actual conditions. The ranges of EFs of water soluble ions and elements were 4.68-50.2 mg·kg-1 fuel and0.634-11.2 mg·kg-1 fuel, respectively. Cr, Ni, Cu and Zn mainly come from the diesel combustion emission, but Ca, Mg, Fe, Ti and V mainly come from the lubricate oil discharge. The ranges of EFs of alkanes, polycyclic aromatic hydrocarbons, hopane and sterane were 0.013-0.133, 7.19-40.5, 0.053-2.95 mg·kg-1 fuel, respectively. The alkanes showed unimodal distribution, the maximum carbon atoms in C19 and C20, and the ranges of CPI, LMW/HMW were 0.897-1.21 and 16.2-47.7. Four ring PAHs accounted for 70.1%-82.5% of PAHs, and the PAHs characteristic ratio indicates that the PAHs emitted from diesel combustion and volatile. Total of 17A（H）-21B（H）-30-Norhopane and 17A（H）-21B（H）-Hopane accounted for 69.4%-82.7% of total hopane and sterane.The ranges of PM EFs for six excavators at work, idle and walking operations were 97.8-2,750, 75.3-1,336 and 75.0-636 mg·kg-1 fuel. Excavator’s maximum PM EF was 4.4 times higher than that of diesel truck. The excavators PM EFs were higher than that of foreign non road sources PM emission standards and partially exceed Chinese non-road sources standards 2. The average EFs of PM were in the order of working>idle>walking. PM EFs for excavators was decreased by 58% from national non-road emission standards pre-1 to 2. The ranges of average EFs of OC, EC, water soluble ions and elements for excavators were 7.24-1,247, 52.1-461, 1.54-16.7, 1.56-8.73 mg kg-1 fuel, respectively. The range of SO2-4/NO-3 was 0.06-0.70<1 and the ratios of Fe/V, Zn/Cu and V/Ni were 0.26±1.13, 0.81±2 and 2,150±2,865, respectively. The range of total alkanes emission factor for four excavators was 10.4-222 mg·kg-1fuel, which was significantly higher than that of diesel trucks. The total PAHs EF of the excavator was equal to the value of the diesel truck. However, the CPI index and characteristic ratios of PAHs in the particulate matter of excavators were different from that of diesel trucks.The EFs of PM2.5 in the WZS tunnel was 70.1 ± 15.9 mg·veh-1·km-1, whereas it was 22.2 ± 6.52 mg·veh-1·km-1 in the KXL tunnel. The proportions of the different constituents in the PM2.5 in the WZS tunnel were OM（33.2%）, EC（32.1%）, elements（13.9%）, and water soluble ions（9.2%）. The chemical profile of PM2.5 in the KXL tunnel was OM（21.2%）, EC（10.4%）, elements（8.90%）, and water soluble ions（8.87%）. The EFs of PM2.5、SO2-4 and Pb were decreased by vehicle emission standards and fuel quality policy in China. In addition, The PM2.5 EFs of gasoline vehicles and diesel vehicles calculated by the tunnel tests were 7.36±6.51 and 415±52 mg·veh-1·km-1, respectively. The results of tunnel test were compared with chassis dynamometer and on-road studies, and it is found that the experimental results of the three methods were different. The results of the chassis dynamometer test were different with the others mostly. Finally, the PM2.5 emissions from the vehicles in Yantai during 2008-2013 were 246±218 ton to 840±743 ton for gasoline vehicles, and 13,825±1,732 ton to 23,042±2,887 ton for diesel vehicles, respectively. |
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