新型碳质气溶胶(OC/EC)观测方法的应用效果分析  

Application effect analysis of new carbonaceous aerosol(OC/EC) observation method

作　　者：任磊 曹芳[1,2] 王剑琼 张煜娴 谢添 罗文昭 谢锋 章炎麟 REN Lei;CAO Fang;WANG Jianqiong;ZHANG Yuxian;XIE Tian;LUO Wenzhao;XIE Feng;ZHANG Yanlin(Center of Atmospheric Environment,International Joint Laboratory on Climate and Environment Change,Nanjing University of Information Science&Technology,Nanjing 210044,China;School of Applied Meteorology,Nanjing University of Information Science&Technology,Nanjing 210044,China;China Global Atmosphere Watch Baseline Observatory,Xining 810001,China)

机构地区：[1]南京信息工程大学气候与环境变化国际合作联合实验室大气环境中心,南京210044 [2]南京信息工程大学应用气象学院,南京210044 [3]中国大气本底基准观象台,西宁810001

出　　处：《环境工程学报》2022年第9期3017-3030,共14页Chinese Journal of Environmental Engineering

基　　金：国家自然科学基金资助项目(41977305,41977185);江苏省创新创业团队项目。

摘　　要：为探究新型碳气溶胶组分在线分析系统(CASS)对大气中碳质气溶胶测量的准确性和实用性,将CASS系统与在线SUNSET OC/EC分析仪测量结果进行了对比,并应用CASS系统对南京2020年秋季大气碳质气溶胶的组分进行了分析。结果表明:在南京北部郊区秋季用CASS系统测量,其黑碳(BC)与元素碳(EC)的计算系数为0.78;经校正后的CASS系统所测得的总碳(TC)、有机碳(OC)和EC结果与在线SUNSET OC/EC分析仪的测量结果具有较好的一致性,斜率分别为1.04 (R^(2)=0.9)、0.87 (R^(2)=0.92)、1.05 (R^(2)=0.92),2台仪器的各个碳质组分的测量误差在10%以内;OC和EC分别占PM的32%和10%左右,二次有机碳(SOC)占OC的38%左右;EC主要来源为化石燃料燃烧(占比约80%);棕碳(BrC)在370 nm处的光吸收占比为21.18%±6.91%,一次排放污染物居多。综上所述,经过校正后的CASS系统与传统的热光法SUNSET OC/EC分析仪相比,两者的测量结果较为一致;CASS可以分析EC的来源,也可以计算棕碳的吸光占比;CASS具有独特的载气功能以及测量方法,维护和移动观测更加方便,且更加适合于偏远地区。本研究成果可为CASS系统在大气污染监测中的推广应用提供参考。In order to explore the accuracy and practicability of measuring carbonaceous aerosols in the atmosphere by the new carbonaceous aerosol speciation system(CASS), a contrastive study of measuring results between CASS system and the online SUNSET OC/EC analyzer was conducted, and the former was used to analyze carbonaceous aerosols in Nanjing in autumn of 2020. The results showed that the calculation coefficient of internal black carbon(BC) and elemental carbon(EC) was 0.78. The total carbon(TC), organic carbon(OC)and EC determined by the calibrated CASS system were in good agreement with those by the online SUNSET OC/EC analyzer with respective slope of 1.04(R^(2)=0.9), 0.87(R^(2)=0.92), and 1.05(R^(2)=0.92), and the measurement errors of each carbonaceous component determined by the two instruments were within 10%. In addition, OC and EC accounted for about 32% and 10% of PM, respectively, and secondary organic carbon(SOC) accounted for about 38% of OC. The main source of EC was fossil fuel combustion with a ratio of about80%. The ratio of light absorption by brown carbon(BrC) at 370 nm was(21.18±6.91)%, which was mainly the primary emission pollutant. Overall, the measurement results of the calibrated CASS were consistent with those of the traditional thermal-optical SUNSET OC/EC analyzer, and the former could analyze the source of EC and the light absorption ratio of brown carbon at 370nm. In addition, the unique gas-carrying function and measurement method in CASS made it more convenient for maintenance and mobile observation, as well as more suitable for remote areas. The research results can provide a reference for the popularization and application of CASS in air pollution monitoring.

关 键 词：碳质气溶胶 碳气溶胶组分在线分析系统(CASS) 热光法 SUNSET OC/EC分析仪 对比分析 

分 类 号：X513[环境科学与工程—环境工程]