Takeuchi J.,Institute for Environmental Protection |
Inoue T.,Kawasaki Global Environment Knowledge Center
Journal of Global Environment Engineering | Year: 2010
Water-soluble components in high concentrations of suspended particulate matter (SPM: particles less than 10 urn in size) were analyzed to understand the formation of secondary inorganic particles. This analysis was carried out by using the tape filters of an automatic sampler of SPM at a monitoring station in Kawasaki city. The generation and transportation of secondary inorganic particles in Case I (April 12 and 13,2006) and Case II (April 18 and 19,2006) was discussed considering the relationship between the ion concentrations, simultaneously measured gas concentrations, and the results of the backward trajectory analysis of an air parcel. In Case I, it was found that the concentration of NO3 - increased and the concentration of Cl-decreased in high concentrations of SPM. From these findings, it was inferred that secondary inorganic particles that were formed by the absorption of gaseous HNO3 into sea-salt particles in humid air contributed to the increase in die concentrations of SPM. In Case II, it was found that the concentrations of SO4 2-and Ca2+ increased in the concentrations of SPM. The results of the backward trajectory analysis of an air parcel showed that the air parcel was transported from the Asian Continent to the Kanto Plain in Japan. Therefore, it was inferred that the Asian dust from the Asian Continent contributed to the high concentrations of SPM. In addition, it was shown that the results from the tape filters and the practical use of relative data were useful in understanding the generation and transportation of secondary inorganic particles.