Online Source Analysis of Particulate Matter (PM2.5) in a Heavy Pollution Process of Shijiazhuang City During Heating Period in 2015

Abstract

In recent years, more and more public attention has been paid to the problem of air pollution during the heating period in North China. This article took a heavy pollution process of Shijiazhuang district from Nov.24th to Dec.4th in 2015 as an example, and analyzed comprehensively the source apportionment in different periods, size distribution of the PM2.5 from each source in different periods, the characteristics of mass spectra of the main emission sources and the meteorological conditions with the method of real-time online source analysis. It turned out:the main sources of pollutants were coal combustions, industrial discharges, vehicle exhausts and secondary inorganic reactions. With the help of meteorological condition of low pressure and low wind speed, the PM2.5 mainly produced by coal combustions and industrial discharges accumulated heavily and went through the second stage conversion, leading to this heavy air pollution. The main particulate matters from coal combustions were the mixed carbons; the main particulate matters from industrial discharges were metals; the main particulate matters from vehicle exhausts were elemental carbon and manganese metal; the main particulate matters from pure secondary inorganic sources were secondary inorganic ions; the main particulate matters from dust pollution were aluminum, calcium, iron and silicate minerals; the main particulate matters from biomass fuel combustions were levoglucosan; the feature signal from restaurant discharges was organic acid. Different from the distribution before and after the heavy pollution period, the particulate matters from the 8 pollution sources presented even distribution during the heavy pollution period.