Measurement on PM and its chemical compositions for real-world emissions from non-road and on-road diesel vehicles
Min Cui1, Yingjun Chen1, Cheng Li2, Junyu Zheng2, Chongguo Tian3, Caiqing Yan4, and Mei Zheng41Key Laboratory of Cities' Mitigation and Adaptation to Climate Change in Shanghai (China Meteorological Administration), College of Environmental Science and Engineering, Tongji University, Shanghai, China 2Laboratory for Atmospheric Research and Environmental Simulation, School of Environment and Energy, South China University of Technology, Guangzhou, China 3Key Laboratory of Coastal Zone Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, China 4State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, China
Received: 22 Nov 2016 – Accepted for review: 05 Dec 2016 – Discussion started: 06 Dec 2016
Abstract. With increasing population of both non-road and on-road diesel vehicles, the adverse effects of PM and its compositions (such as elemental carbon (EC), polycyclic aromatic hydrocarbons (PAHs)) on air quality and human health get more and more attention. However, characteristics of PM and its compositions emitted from diesel vehicles, particularly measured under real-world condition, are scarce. In this study, six excavators and five trucks, involving wide-range emission standards and working in different operating modes, were tested to characterize constituents of PM (including organic carbon (OC), EC, water soluble ions (WSIs), elements, and organic species such as PAHs, n-alkanes, hopanes and steranes). The average emission factors of PM (EFPM) for excavators and trucks were 829 ± 806 and 498 ± 234 mg kg−1 fuel, respectively, which are comparable with other studies. However, EFPM was significantly affected by fuel quality, operating modes and emission standards. High correlation (R2 = 0.79, p < 0.01) existed between the EFPM for excavators and the sulfur contents in fuel. The highest average EFPM under working mode for excavators was 904 ± 979 mg kg−1 fuel due to high engine load under this mode. From pre-stage 1 to stage 2 excavators, the average EFPM for excavators with different emission standards decreased by 58 %. Similarly, for trucks the average EFPM under non-highway condition (548 ± 311 mg kg−1 fuel) was higher than those under highway condition (497 ± 231 mg kg−1 fuel). Meanwhile, reductions from China II and China III to China IV trucks were 63.5 % and 65.6 %, respectively. Generally, PM compositions emitted from excavators dominated by OC (39.2 % ± 21.0 %), EC (33.3 % ± 25.9 %), and while for trucks, PM dominated by EC (26.9 % ± 20.8 %), OC (9.89 % ± 12 %) and WSIs (4.67 % ± 5.74 %). Several differences of compositions were observed among various operating modes, emission standards and fuel quality. The average OC / EC ratios under idling and working modes for excavators were 3 and 4 times higher than those in moving modes. Although EFPM for excavators and trucks reduced with stringent emission standards, the fractions of elements for excavators ranged from 0.49 % to 3.03 % from pre-stage 1 to stage 2, and fraction of WSIs for China IV truck was 6 fold higher than those from other trucks. Furthermore, compared with the results from other diesel vehicles, wide ranges of ratios of BaA / (BaA+Chry) (0.26–0.86), IcdP / (IcdP+BghiP) (0.20–1.0) and Flua / (Flua+Pry) (0.24–0.87) for excavators were found, which may be attributed to the complex of operating modes for excavators. Although fractions of total 16 PAHs for excavators and trucks were similar, the total of BaPeq that was used to evaluate the carcinogenic risk was 31 times higher than those for trucks. Therefore, more attention should be paid to non-road vehicle's emission.
Cui, M., Chen, Y., Li, C., Zheng, J., Tian, C., Yan, C., and Zheng, M.: Measurement on PM and its chemical compositions for real-world emissions from non-road and on-road diesel vehicles, Atmos. Chem. Phys. Discuss., doi:10.5194/acp-2016-1038, in review, 2016.