唐山市2019-2020年细颗粒物组分特征及来源解析

Composition Characteristics and Source Analysis of Fine Particulate Matter in Tangshan From 2019 to 2020

为探究唐山市PM_(2.5)的污染特征及来源,推动空气质量持续提高,基于2019-2020年唐山市PM_(2.5)及其化学组分浓度数据,分析其变化规律及污染特征,并运用正定矩阵因子模型(PMF)解析污染来源。结果表明:研究期间唐山市PM_(2.5)呈现总体改善的趋势,但PM_(2.5)年均浓度仍超过国家二级标准,是大气污染防治的主要对象;研究期间,PM_(2.5)中含碳组分占比为19.75%~20.29%,其中OC达到了3/4,3种无机盐组分年均浓度共占PM_(2.5)浓度的70%以上,NO-3占比最大;无机元素共占PM_(2.5)的5%~6%,PM_(2.5)及其组分年均浓度时间变化大体一致,呈下降趋势。源解析结果表明,唐山市PM_(2.5)污染源主要有6个来源:二次气溶胶、扬尘源、生物质燃烧、燃煤源、机动车尾气及工业冶炼尘。整体上来看,唐山市大气PM_(2.5)主要受二次气溶胶、燃煤源和机动车尾气排放影响,其中,影响最大的污染源为二次气溶胶,且受钢铁焦化企业和大宗物料运输等影响,燃煤和机动车尾气对唐山市PM_(2.5)影响也较大。

In order to explore the pollution characteristics and sources of fine particulate matter(PM_(2.5))in Tangshan,and promote the continuous improvement of air quality,based on the concentration data of fine particulate matter and its chemical components in Tangshan from 2019 to 2020,this paper analyzed its change rules and pollution characteristics,and applied the positive matrix factor model(PMF)to analyze the pollution sources.The results showed that PM_(2.5) showed an overall improvement trend during the study period,but the average annual concentration of PM_(2.5) still exceeded the national secondary standard,and PM_(2.5) was the main object of air pollution prevention and control.During the study period,the proportion of carbon components in PM_(2.5) ranged from 19.75%to 20.29%,in which OC reached three quarters.The average annual concentration of three inorganic salt components accounted for more than 70%of PM_(2.5) concentration,and NO-3 accounted for the largest proportion.Inorganic elements accounted for 5%to 6%of PM_(2.5).The time variation of the annual average concentration of PM_(2.5) and its components were generally consistent,showing a downward trend.The source analysis results showed that there were six main sources of PM_(2.5) pollution in Tangshan:secondary aerosol,dust source,biomass combustion,coal source,motor vehicle exhaust and industrial smelting dust.On the whole,the atmospheric PM_(2.5) in Tangshan were mainly affected by secondary aerosols,coal sources and vehicle exhaust emissions.Among them,the most influential pollution source was secondary aerosol.Affected by steel coking enterprises and bulk material transportation,coal burning and motor vehicle exhaust also had a greater impact on PM_(2.5) in Tangshan.