| Carbonaceous aerosols,a major component of fine particulate matter,and had adverse effects on the environment,vis ibility,climate and human health.Taiyuan Bas in was an important coal industry base in China.Due to the restriction of industrial structure and topography,atmospheric particulate matter has been in a high level.Knowing the pollution characteristics of fine particulate matter(PM2.5)and carbonaceous components in Taiyuan Basin was of great significance for effectively controlling of atmospheric pollution and improving the environmental quality in the region.In view of the current pollution situation,the concentrations of organic carbon（OC）and elemental carbon（EC）in PM2.5were measured by using an online OC/EC analyzer from April 2020 to March2021 in a county of Taiyuan Basin,and characteristics and sources of OC and EC were analyzed.The main conclusions were as follows:（1）The average values of OC and EC were 4.82μg/m3 and 2.00μg/m3,accounting for 8.91%and 3.70%of PM2.5 mass respectively.The linear fitting correlation coefficient of OC and EC was 0.81,indicating that the sources of OC and EC in this region were similar,further indicating that carbonaceous aerosol in this region was greatly affected by primary emission sources.（2）The concentration of SOC estimated by the MRS（Minimum R Squired method,MRS）method was 1.73μg/m3 in this study,accounted for about 36.11%of the OC.Pronounced double-peak diurnal patterns occurred in fall and winter,while only one peak occured in the morning in spring and summer,which was mainly due to the pollution sources such as coal burning activities and adverse diffusion conditions in autumn and winter.（3）The correlation between carbonaceous components and CO and SO2 in spring was greater than NO2,which indicated that the contribution of coal combustion to carbonaceous aerosol was higher than vehicle emission.SOC was significantly correlated with O3 in summer,indicated that photochemical reactions was favorable for SOC formation.The correlation coefficients of SO2,NO2,CO with EC and POC（R2 all above 0.6）in autumn and winter were significantly higher than those in other seasons,while the correlation coefficients with SOC were lower spring and summer,indicated that carbonaceous aerosol in autumn and winter were mainly emitted by primary emissions.（4）Wind direction wind speed analysis showed that most of the high mass concentration values of carbonaceous components in PM2.5 occured in the northeast and southeast directions,indicated that EC,POC and SOC were mainly affected from these directions.The influencing factors of SOC formation in different seasons was investigated in the present work.It is concluded that SOC were mainly affected by aqueous-phase reactions in spring,and the photochemical reactions had a great contribution to SOC in summer,and affected by both in winter.（5）The results indicated that the total emissions of OC and EC from anthropogenic sources in 2020 were 453.45t and 447.97t respectively,among them coal combustion and coking were the highest.And accounted for 27.86%and 26.09%of OC and 46.01%and 22.65%of EC,respectively,which were significantly higher than other pollution sources. |
PDF Full Text Request