A Study on Particulate Matter Footprint Calculation on Transportation Modes

Abstract

Objective : In this study, we proposed the concept of the particulate matter footprint (PM Footprint) and assessed the PM Footprint in transportation modes (road, rail, and water transportation). In addition, we assessed the contribution of secondary particulate matter formation gas emissions, which contribute to particulate matter formation.Method : To calculate the PM Footprint in the transportation sector, the ReCiPe life cycle impact assessment method in life cycle assessment (LCA) was used. For the PM Footprint of each transportation mode, the life cycle inventory data were multiplied by the characterization factors of PM<sub>10</sub>, PM<sub>2.5</sub> and secondary particulate matter formation emissions such as NOx, SOx, NH<sub>3</sub>. The PM Footprint values were shown in kg PM<sub>2.5</sub> eqv. value.Results and Discussion : The road transportation (trucks) had a much higher PM Footprint value than rail and water transportation in tkm unit based. In the road transportation mode, small size truck such as 3.5 tons (1.37E-03 kg PM<sub>2.5</sub> eqv./tkm), 3.51~5 tons (9.65E-04 kg PM<sub>2.5</sub> eqv./tkm), 1.25 tons (8.38E-04 kg PM<sub>2.5</sub> eqv./tkm), and 1 ton (7.83E-04 kg PM<sub>2.5</sub> eqv./tkm) had higher PM Footprint value than big size trucks. In the rail transportation mode, the diesel rail transportation had the highest PM Footprint value, followed by electric + diesel rail transportation and electric rail transportation. In the water transportation mode, the tanker LNG_100 dwt had the highest PM Footprint value, followed by ro-ro ship coastal, and tanker coastal 500~20,000 dwt. The secondary particulate matter formation emissions (NOx, SOx, NH<sub>3</sub>) contributed to PM Footprint value with 59% in road transportation, 80% in rail transportation, and 61% in water transportation. Conclusions : The PM Footprint values, which shown in this study and the results of the directed polluted PM and secondary gas emissions should be considered for national PM reduction policy and planning. Finally, a certification system using the PM Footprint in this study should be developed and settled down for national PM reduction.